Atoms and Molecules

Multiple Choice Questions

1. Which of the following correctly represents 360g of water?

(i) 2 moles of H20

(ii) 20 moles of water

(iii) 6.022×1023 molecules of water

(iv) 1.2044×1025 molecules of water

(a) (i)

(b) (i) and (iv)

(c) (ii) and (iii)

(d) (ii) and (iv)

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Answer

Answer is (d) (ii) and (iv)

Explanation:

Number of moles = Mass of water  Molar mass of water 

Number of moles =360g 18g/mol

Number of moles =20

Number of molecules =20×6.022×1023=1.2044×1025 molecules of water

Thus, option (d) is correct.

2. Which of the following statements is not true about an atom?

(a) Atoms are not able to exist independently

(b) Atoms are the basic units from which molecules and ions are formed

(c) Atoms are always neutral in nature

(d) Atoms aggregate in large numbers to form the matter that we can see, feel or touch

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Answer

Answer is (d) Atoms aggregate in large numbers to form the matter that we can see, feel or touch

Explanation:

Atoms aggregate in large numbers to form the matter But we cannot see the matter with our naked eyes.

3. The chemical symbol for nitrogen gas is

(a) Ni

(b) N2

(c) N+

(d) N

Show Answer

Answer

Answer is (b) N2

Explanation:

Chemical formula of Nitrogen is N but Nitrogen exist in molecule of two ions hence chemical symbol of Nitrogen is written as N2.

4. The chemical symbol for sodium is

(a) So

(b) Sd

(c) NA

(d) Na

Show Answer

Answer

Answer is (d) Na

Explanation:

Sodium word is derived from Latin word Natrium hence the chemical name of sodium is Na.

5. Which of the following would weigh the highest?

(a) 0.2 mole of sucrose (C12H22O11)

(b) 2 moles of CO2

(c) 2 moles of CaCO3

(d) 10 moles of H2O

Show Answer

Answer

Answer is (c) 2 moles of CaCO3

Explanation:

Weight of a sample in grant = Number of moles x Molar mass

(a) 0.2 moles of Ci2H220,=0.2×342=68.4g

(b) 2 moles of CO is 2x44 is. 88g

(c) 2 moles of CaCO? 2 x IIMI - 200g (4) 10 moles of I-120 = 10 x 18 - 1St g

Hence, option (c) is correct.

6. Which of the following has maximum number of atoms?

(a) 18g of H2O

(b) 18g of O2

(c) 18g of CO2

(d) 18g of CH4

Show Answer

Answer

Answer is (d) 18g of CH4

Explanation:

Number of atoms = substance × Number of atoms in the molecule/ Molar mass × NA

(a) 18g of water =18×3/18×NA=3NA

(b) 18g of oxygen =18×2/32×NA=1.12NA

(c) 18g of CO2=18×3/44×NA=1.23NA

(d) 18g of CH4=18×5/16×NA=5.63NA

Note: NA=6.023×1023

7. Which of the following contains maximum number of molecules?

(a) 1gCO2

(b) 1g N2

(c) 1gH2

(d) 1gCH4

Show Answer

Answer

Answer is (c) 1gH2

Note: NA =6.023×1023

Explanation:

1g of H2=1/2×NA=0.5NA=0.5×6.022×1023=3.011×1023

8. Mass of one atom of oxygen is

(a) 16/6.023×1023g

(b) 32/6.023×1023g

(c) 3/6.023×1023g

(d) 8u

Show Answer

Answer

Answer is (a) 2316 g 6.02310×

Explanation:

Mass of one atom of oxygen = Atomic mass /NA=16/6.023×1023g

Note: NA=6.023×1023

9. 3.42g of sucrose are dissolved in 18g of water in a beaker. The number of oxygen atoms in the solution are

(a) 6.68×1023 (b) 6.09×1022 (c) 6.022×1023 (d) 6.022×1021

Show Answer

Answer

Answer is (a) 6.68×1023

Explanation:

1 mol of sucrose (C12H22O11) contains =11×NA atoms of oxygen, where NA=6.023×1023

0.01mol of sucrose (C12H22O11) contains =0.01×11×NA atoms of oxygen

=0.11×NA atoms of oxygen

=18g/(1×2+16)gmol1

=18g/18gmol1

=1mol

1mol of water (H2O) contains 1×NA atom of oxygen

Total number of oxygen atoms =

Number of oxygen atoms from sucrose + Number of oxygen atoms from water

=0.11NA+1.0NA=1.11NA

Number of oxygen atoms in solution =1.11× Avogadro’s number

=1.11×6.022×1023=6.68×1023

10. A change in the physical state can be brought about

(a) only when energy is given to the system

(b) only when energy is taken out from the system

(c) when energy is either given to, or taken out from the system

(d) without any energy change

Show Answer

Answer

Answer is (c) when energy is either given to, or taken out from the system

Short Answer Questions

11. Which of the following represents a correct chemical formula? Name it.

(a) CaCl

(b) BiPO4

(c) NaSO4

(d) NaS

Show Answer

Answer

Answer is (b) BiPO4, Its name is Bismuth Phosphate

Explanation:

Bismuth phosphate is right because Both ions are trivalent Bismuth phosphate(Bi3+- Trivalent anion. anion is an ion that is negatively charged).

12. Write the molecular formulae for the following compounds

(a) Copper (II) bromide

(b) Aluminium (III) nitrate

(c) Calcium (II) phosphate

(d) Iron (III) sulphide

(e) Mercury (II) chloride

(f) Magnesium (II) acetate

Show Answer

Answer

Answers are

(a) Copper (II) bromide- CuBr2

(b) Aluminium (III) nitrate =Al(NO3)3

(c) Calcium (II) phosphate - Ca3(PO4)2

(d) Iron (III) sulphide - Fe2S3

(e) Mercury (II) chloride - HgCl2

(f) Magnesium (II) acetate- Mg(CH3COO)2

13. Write the molecular formulae of all the compounds that can be formed by the combination of following ions Cu2+,Na+,Fe3+,C1SO42,PO43

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Answer

Answers are

CuCl2/CuSO4/Cu3(PO4)2

NaCl/Na2SO4/Na3PO4

FeCl3/Fe2(SO4)3/FePO4

14. Write the cations and anions present (if any) in the following compounds

(a) CH3COONa

b) NaCl

(c) H2

(d) NH4NO3

Show Answer

Answer

a) In CH3COONaCH3COO is anion and Na is cation.

b) In NaClCl anion Na is cation

c) In H2 both the ions are cations as they share electrovalent bond between them

d) In NH4NO3NO3 is anion NH4 is cation

15. Give the formulae of the compounds formed from the following sets of elements

(a) Calcium and fluorine

(b) Hydrogen and sulphur

(c) Nitrogen and hydrogen

(d) Carbon and chlorine

(e) Sodium and oxygen

(f) Carbon and oxygen

Show Answer

Answer

(b) Hydrogen and sulphur- H2S - Hydrogen Sulphide

(c) Nitrogen and hydrogen- NH3 - Ammonia

(d) Carbon and chlorine CCl4 - Carbon Tetra chloride

(e) Sodium and oxygen - Na2O-Sodium Oxide

(f) Carbon and oxygen- CO2; CO- Carbon-di-oxide; Carbon Monoxide

16. Which of the following symbols of elements are incorrect? Give their correct symbols

(a) Cobalt CO

(b) Carbon c

(c) Aluminium AL

(d) Helium He

(e) Sodium So

Show Answer

Answer

Cobalt CO is wrong, correct symbol is Co

Carbon c is wrong, correct symbol is C

Alluminium AL is wrong, correct symbol is Al

Helium He is the right symbol

Sodium So is wrong, correct symbol is Na

17. Give the chemical formulae for the following compounds and compute the ratio by mass of the combining elements in each one of them. (You may use appendix-III).

(a) Ammonia

(b) Carbon monoxide

(c) Hydrogen chloride

(d) Aluminium fluoride

(e) Magnesium sulphide

Show Answer

Answer

Sl. No. Compounds Chemical formula Ratio by mass of the
combining elements
(a) Ammonia NH3 N:H=14:3
(b) Carbon monoxide CO C:O=12:16=3:4
(c) Aluminium fluoride HCl H:Cl=1:35.5
(d) Aluminium fluoride AlF3 Al:F=27:57=9:19
(e) Magnesium sulphide MgS Mg:S=24:32=3:4
18. State the number of atoms present in each of the following chemical species

(a) CO32

(b) PO43

(c) P2O5

(d) CO

Show Answer

Answer

(a) CO21+3=4

(b) PO31+4=5

(c) P2O52+5=7

(d) CO1+1=2

19. What is the fraction of the mass of water due to neutrons?

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Answer

Mass of 1 mole of a substance is equal to its relative atomic or molecular mass in grams.

Mass of one mole (Avogadro Number) of neutrons =1g

Mass of one neutron =1 / Avogadro number(NA) g

Mass of one molecule of water = Molar mass /NA=18/NAg calculated by multiplying the atomic weight of hydrogen (1.008) by two and adding the result to the weight for one oxygen (15.999)

Mass of one molecule of water = Molar mass /NA=18/NAg

Avogadro number (NA)=6.022×1023mol1

There are 8 neutrons in one atom of oxygen

Number of neutrons in oxygen= number of oxygen - Atomic number of oxygen

Oxygen’s atomic weight =15.9994

increases with an increase in temperature.

Therefore the mass is 16

Therefore number of neutrons =168=8

Mass of one neutron =1 / Avogadro number(NA) g

Mass of 8 neutrons =8/ Avogadro number(NA) g

Fraction of mass of water due to neutrons =8/18g

20. Does the solubility of a substance change with temperature? Explain with the help of an example.

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Answer

Solubility is the ability of a solute to get dissolved in 100g solvent. Solubility of a given solute to dissolve in specific solvent depends on the temperature. With Increase in temperature solubility of liquids and solids increase. In the same way solubility of gases decreases with increase in temperature.

Ex: Sugar dissolves faster in hot water than in cold water.

21. Classify each of the following on the basis of their atomicity.

(a) F2

(b) NO2

(c) N2O

(d) C2H6

(e) P4

(f) H2O2

(g) P4010

(H) O3

(i) HCl

(j) CH4

(k) He

(l) Ag

Show Answer

Answer

a) Monoatomic are inert gases that do not combine and exist as monoatomic gases

b) Diatomic- (a) 2 - diatomic- NO2=1+2=3.,HCl=1+1=2

c) Triatomic-N2O =2+1=3.,NO2=1+2=3,O3=3

d) Tetraatomic- H2O2=2+2=4,P4O10=4+10=14,P4=4,CH4=1+4=5

e) Octa atomic- C2H6=2+6=8

f) Polyatomic.

22. You are provided with a fine white coloured powder which is either sugar or salt. How would you identify it without tasting?

To examine if the fine white coloured powder is sugar pr salt we can conduct two experiments.

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Answer

1. Heating: Upon heating sugar melts to liquid form because sucrose has a decomposition point and melting point at temperatures between 190 to 192 degrees Celsius. This will turn sugar to light brown colour. Upon heat further sugar gets charred to black colour.

Salt has a melting point of 841 degrees Celsius and 1545.8 degrees Fahrenheit. If we don’t heat it to that point nothing change is observed.

2. Electric conductivity:

If we dissolve the given substance in water we can check for electric conductivity to check whether the substance is sugar or salt. If it is salt it conducts electricity. Because salt (NaCl) has positive sodium ions and negative chloride ions hence salt conducts electricity. But sugar don’t conduct electricity as sugar has only positive ions.

23. Calculate the number of moles of magnesium present in a magnesium ribbon weighing 12g. Molar atomic mass of magnesium is 24gmol1.

Show Answer

Answer

Number of moles = weight 

atomic weight

=1224=0.5 moles

Long Answer Questions

24. Verify by calculating that (a) 5 moles of CO2 and 5 moles of H2O do not have the same mass. (b) 240g of calcium and 240g magnesium elements have a mole ratio of 3:5.

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Answer

(a) Molar mass of CO2 =12+2×16=12+32=44gmol1

5 moles of CO2 have mass =44×5=220g

Similarly, molar mass of H2O=2x1+16=18gmol1

5 moles of H2O

x5=90g

It is verified that 5 moles of CO2 and 5 moles of H2O are not same.

(b) Number of moles =w/ atomic weight

Atomic weight of Ca=40amu

Number of moles in 240g Ca metal 240/ 40=6

Number of moles in 240g of Mg metal 240/24 =10

Atomic weight of Mg=24amu

Ratio 6:10

25. Find the ratio by mass of the combining elements in the following compounds. (You may use Appendix-III) (a) CaCO3 (d) C2H5OH (b) MgCl2 (e) NH3 (c) H2SO4 (f) Ca(OH)2

Show Answer

Answer

a) CaCO3

Ca: C:O×3

40:12:16×3

40: 12:48

10:3:12

(b) MgCl2

Mg:Cl×2

24: 35.5×2

24: 71

(c) H2SO4

H×2:S:O×4

2: 32:16×4

2:32:64

1: 16:32

(d) C2H5OH

C×2:H×6:O

12×2:1×6:16

24:6:16

12:3:8 (e) NH3

N:H×3

14:1×3

14: 3

(f) Ca(OH)2

Ca:O×2:H×2

40:16×2:1×2

40:32:2

20:16:1

26. Calcium chloride when dissolved in water dissociates into its ions according to the following equation. CaCl2(aq)Ca2+(aq)+2Cl(aq) Calculate the number of ions obtained from CaCl2 when 222g of it is dissolved in water.

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Answer

1 mole of calcium chloride =111g

Therefore 222g of CaCl2 is equivalent to 2 moles of CaCl2

Since 1 formula unit CaCl2 gives 3 ions,

therefore, 1mol of CaCl2 will give 3 moles of ions 2 moles of CaCl2 would give 3×2=6 moles of ions.

No. of ions = No. of moles of ions × Avogadro number

=6×6.022×1023

=36.132×1023

=3.6132×1024 ions

27. The difference in the mass of 100 moles each of sodium atoms and sodium ions is 5.48002g. Compute the mass of an electron.

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Answer

Sodium atom and ion differ by one electron. For 100 moles each of sodium atoms and ions there would be a difference of 100 moles of electrons.

Mass of 100 moles of electrons =5.48002g

Mass of 1 mole of electron =5.48002/100g

Mass of one electron =5.48002/100×6.022×1023

=9.1×1028g

=9.1×1031kg

28. Cinnabar (HgS) is a prominent ore of mercury. How many grams of mercury are present in 225g of pure HgS ? Molar mass of Hg and S are 200.6g mol-1 and 32g mol-1 respectively.

Show Answer

Answer

Molar mass of HgS= The molar mass of Hg+ the molar mass of S

=200.6+32=232.6gmol1

1 molecule of HgS contains 1 atom of Hg

232.6g of HgS contains 200.6g of Hg

Therefore, Mass of Hg in 225g of HgS=200.6 X 225=194.04g

232.6

29. The mass of one steel screw is 4.11g. Find the mass of one mole of these steel screws. Compare this value with the mass of the Earth (5.98×1024kg). Which one of the two is heavier and by how many times?

Show Answer

Answer

One mole of screws weigh =2.475×1024g

=2.475×1021kg

Mass of the Earth / Mass of 1 mole of screws =5.98×1024kg

$ 2. 475 \times 10^{21} $

Mass of earth is 2.4×103 times the mass of screws

=2.4×10

The earth is 2400 times heavier than one mole of screws

30. A sample of Vitamin C is known to contain 2.58×1024 oxygen atoms. How many moles of oxygen atoms are present in the sample?

Show Answer

Answer

We know,

1 mole =6.022×1023

The number of moles = Given number of particles

Avogadro Number

n=2.58×10246.022×1023

n=4.28mol

31. Raunak took 5 moles of carbon atoms in a container and Krish also took 5 moles of sodium atoms in another container of same weight.

(a) Whose container is heavier?

(b) Whose container has more number of atoms?

Show Answer

Answer

a) Mass of sodium atoms carried by Krish =(5×23)g=115g

Atomic weight of Na=23

While mass of carbon atom carried by Raunak =(5×12)g=60g

b) Thus, Krish’s container has more number of atoms

32. Fill in the missing data in the Table 3.1

Species
property
H2O CO2 Na atom MgCl2
No of Moles 2 - - 0.5
No of particles - 3.011×1023 - 0
Mass 36g - 115g 0

Show Answer

Answer

Species property H2O CO2 Na atom MgCl2
No of Moles 2 0.5 5 0.5
No of particles 12.044×1024 3.011×1023 3.011×1023 3.011×1023
Mass 36g 22g 115g 47.5g
33. The visible universe is estimated to contain 1022 stars. How many moles of stars are present in the visible universe?

Show Answer

Answer

Number of moles of stars =1022

6.023×1023

=0.0166 moles 

34. What is the SI prefix for each of the following multiples and submultiples of a unit?

(a) 103

(b) 10-1

(c) 10-2

(d) 10-6

(e) 10-9

(f) 10-12

Show Answer

Answer

a) 103=1000= kilo

(b) 101=1/10=0.1= deci

(c) 102=1/100=0.01= centi

(d) 106=0.000001= micro

(e) 109=0.000000001= nano

(f) 1012=0.000000000001= pico

35. Express each of the following in kilograms

(a) 5.84×103mg

(b) 58.34g

(c) 0.584g

(d) 5.873×1021g

Show Answer

Answer

(a) 5.84×103mg=5.84×109kg

(b) 58.34g=5.834×102kg

(c) 0.584g=5.84×104kg

(d) 5.873×1021g=5.873×1024kg

36. Compute the difference in masses of 103 moles each of magnesium atoms and magnesium ions. ( Mass of an electron =9.1×1031kg)

Show Answer

Answer

Mg2+ ion and Mg atom differ by two electrons.

103 moles of Mg2+ and Mg atoms would differ by

103×2 moles of electrons

Mass of 2×103 moles of electrons =2×103×6.023×1023×9.1×1031kg 2×6.022×9.1×105kg

109.6004×105kg

1.096×103kg

37. Which has more number of atoms? 100g of N2 or 100g of NH3

Show Answer

Answer

No. of moles of atoms = weight / atomic weight.

For N2

100gms of N2=100/2×14 moles =100/28 moles

Number of molecules =100/28×6.022×1023

Molar mass of N2=2x molar mass of monoatomic N

Molar mass of N2=2×14.0067=28 moles.

Number of molecules =100/28×6.022×1023

No. of atoms =2×100/28×6.022×1023=43.01×1023

For NH3 100gm of NH3=

100/17 moles

Number of molecules

=100/17x

6.022×1023 molecules

No. of atoms in NH3=(1+3)=4×100/17×6.022×1023=

141.69×1023 atoms.

Therefore, NH3 has more atoms than N2.

38. Compute the number of ions present in 5.85g of sodium chloride.

Show Answer

Answer

58.5gNaCl contains 6.023×1023 molecules

therefore 58.5gNaCl contains 12.046×1023 ions.

Hence, 5.85gNaCl contains 5.85×12.046×102358.5

=1.2046×1023 ions

39. A gold sample contains 90% of gold and the rest copper. How many atoms of gold are present in one gram of this sample of gold?

Show Answer

Answer

One gram of gold sample will contain 90100=0.9g of gold

Number of moles of gold=mass of gold

atomic mass of gold

=0.919.7

=0.0046

One mole of gold contains NA atoms =6.022×103

Therefore, 0.0046 mole of gold will contain =0.0046×6.022

=2.77×1021

40. What are ionic and molecular compounds? Give examples.

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Answer

While forming some compounds, atoms gain or lose electrons, and form electrically charged particles called ions. Compounds that are formed by the attraction of cations and anions are called as ionic compounds.

Ex. 2 Na+Cl22Na+Cl2NaCl (sodium chloride- common salt.)

Sodium is a group 1 metal, thus forms a +1 charged cation. Chlorine is a non-metal, and has the ability to form a 1 charged anion.

Compounds formed due to bonding of uncharged ions are called as molecular compounds and the bonding between them is called covalent bonding. Molecular compounds are formed by sharing of electrons between the two atoms and the elements are held together by covalent bonds.

Ex: 2C+O22CO ( Carbon monoxide)

41. Compute the difference in masses of one mole each of aluminium atoms and one mole of its ions. (Mass of an electron is 9.1×1028g ). Which one is heavier?

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Answer

Mass of one mole of Aluminium atom ={13× mass of each electron +13× mass of each proton +14× mass of each neutron }× Avogadro’s constant.

We know, if atoms convert into ions, only transfer of electrons takes place, in Al+3 ion, Aluminium atom loss three electrons,

So,

Mass of Al+3={10× mass of each electron +13× mass of each proton +14× mass of each neutron } Avogadro’s constant

Now,

You see mass of aluminium atom is greater than aluminium ion by 3 electrons

Difference in mass = Mass of Aluminium atom -mass of aluminium ion

=3× mass of each electron x Avogadro’s constant .

=3×9.1×1028×6.023×1023

=27.3×1028×6.023×1023g

=164.4×105g

=1.644×103g

=0.0016g

42. A silver ornament of mass ’ m ’ gram is polished with gold equivalent to 1% of the mass of silver.

Compute the ratio of the number of atoms of gold and silver in the ornament.

Show Answer

Answer

Mass of silver =mg

Mass of gold =m/100g

Number of atoms of silver = Mass/ Atomic mass X NA

=m/108NA Number of atoms of gold

=m/100X197

Ratio of number of atoms of gold to silver =Au:Ag

=m/100X197XNA:m/108 NA

=108:100×197

=108:19700=

1:182.41

43. A sample of ethane (C2H6) gas has the same mass as 1.5×1020 molecules of methane (CH4). How many C2H6 molecules does the sample of gas contain?

Show Answer

Answer

6.02×1023 molecules of methane =1 mole

Hence 1.5×1020 molecules of methane =(1.5×1020×1)÷(6.02×1023) moles

=2.49×104 moles 

Molar mass of Methane (CH4)=12+1x4=16g

Mass of methane = molar mass × no. of moles =16×2.49×104=3.984×103g (This is the same mass as Ethane)

Ethane (C2H6)=12×2+1×6=30

If 30g of Ethane has 6.02×1023 molecules

So 3.984×103g=(3.984×103×6.02×1023)÷30

=8×1019 molecules of Ethane

44. Fill in the blanks

(a) In a chemical reaction, the sum of the masses of the reactants and products remains unchanged. This is called

(b) A group of atoms carrying a fixed charge on them is called

(c) The formula unit mass of Ca3 (PO4)2 is

(d) Formula of sodium carbonate is _and that of ammonium sulphate is

Show Answer

Answer

Answers

a) Law of conservation of mass

b) Ions c) 310

Explanation :

3× atomic mass of Ca+2× atomic mass of phosphorus +8× atomic mass of oxygen) =310

3×40+2×31+8×16=120+62+128=310 d) Na2CO3 and (NH4)2SO4

45. Complete the following crossword puzzle (Fig. 3.1) by using the name of the chemical elements. Use the data given in Table 3.2.

Across Down
The element used by Rutherford during his
α scattering experiment
A white lustrous metal used for making
ornaments and which tends to get tarnished
black in the presence of moist air
An element which forms rust on exposure to
moist air
Both brass and bronze are alloys of the
element
A very reactive non-metal stored under
water
The metal which exists in the liquid state at
room temperature
Zinc metal when treated with dilute
hydrochloric acid produces a gas of this
element which when tested with burning
splinter produces a pop sound.
An element with symbol Pb

Show Answer

Answer

46. (a) In this crossword puzzle (Fig 3.2), names of 11 elements are hidden. Symbols of these are given below. Complete the puzzle. 1. Cl 7. He 2. H 8. F 3. Ar 9. Kr 4. O 10. Rn 5. Xe 11. Ne 6. N

Show Answer

Answer

(a)

b) Six : Helium (He); Neon ( Ne); Argon (Ar); Krypton (Kr); Xenon (Xe); Radon (Rn).

47. Write the formulae for the following and calculate the molecular mass for each one of them.

(a) Caustic potash

(b) Baking powder

(c) Lime stone

(d) Caustic soda

(e) Ethanol

(f) Common salt

Show Answer

Answer

The formulae for the following and calculate the molecular mass for each one of them.

Sl No Compound Formula Molecular mass
A Caustic Potash KOH 39+16+1=56u
B Baking powder NaHCO3 23+1+12+3×16+84u
C Lime stone CaCO3 40+12+3×16+100u
D Caustic soda NaOH2 23+16+1+40u
E Ethanol C2H5OH 2×2+5×1+16+1+46u
F Common Salt NaCl 23+35.5=58.5
48. In photosynthesis, 6 molecules of carbon dioxide combine with an equal number of water molecules through a complex series of reactions to give a molecule of glucose having a molecular formula C6H12O6. How many grams of water would be required to produce 18g of glucose? Compute the volume of water so consumed assuming the density of water to be 1gcm3.

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Answer

6CO2+6H2 O Chlorophyll /Sunlight  arrow C6H12O6+6O2

1 mole of glucose needs 6 moles of water 180g of glucose needs (6×18)g of water 1g of glucose will need 108/ 180g of water.

18g of glucose would need (108/180)×18g of water =10.8g

Volume of water used = Mass Density

=10.8g/1gcm3

=10.8cm3