Stoichiometry

Question 1

Mass of atom depend on_____.

Answer 1

Mass of nucleus (mass of proton+neutron)

Question 2

Different atom have _____ mass and same atom have _____ mass.

Answer 2

Different atom-different mass
same atom-same mass

Question 3

1g of Hydrogen contains ______ molecules.

Answer 3

6.02 x 10^23

Question 4

Avogadro’s number

Answer 4

1mole=6.02 x 10^23 molecules

Question 5

32g of sulphur contains ______ molecules.

Answer 5

6.02 x 10^23

Question 6

16g of oxygen contains ______ molecules.

Answer 6

6.02 x 10^23

Question 7

One mole of given substance contains _____of particles.

Answer 7

6.02 x 10^23 particles

Question 8

Relative atomic mass formula

Answer 8

Relative atomic mass=Avg weighf of one atom/1/12 of mass of carbon-12

Question 9

Do relativeatomic mass have unit?

Answer 9

No
It’s unitless

Question 10

Relative formula Mass(Mr) a

Answer 10

sum of weight of masses of all atomes in a formula

Eg.MgSO4 =Mg+S+4(O)
=24+32+4(16)=120

Question 11

Molar mass

Answer 11

1moleမှာရှိတဲ့Substanceရဲ့mass
Mass of substance of 1mole

Question 12

Molar mass formula

Answer 12

Molar mass=Mass/mole

Question 13

Unit of molar mass

Answer 13

gmol^-1

Question 14

Empirical formula

Answer 14

Simple whole number ratio of atom in a compound

Question 15

Molecular formula

Answer 15

Actual number of atom present in a compound

Question 16

How to find molecular formula?

Answer 16

Molecular formula=empirical unit x empirical formula

Question 17

How to find empirical unit?

Answer 17

Empirical unit=Molecular mass / empirical mass

Question 18

Percentage composition

Answer 18

Percent of atom in a compound

Question 19

Formula for Percentage composition

Answer 19

% composition=total mass of element in compound/total mass of compound x 100%

Question 20

Percentage yield

Answer 20

to compared the actual amy of product obtained in a reaction to the amt of calculation

Question 21

Formula for percentage yield

Answer 21

Percentage yield=Actual yield /Theoratical yield x 100%

Question 22

Theorical yield

Answer 22

max amt of product obtained when 100% of limiting reactant is used.

Question 23

Theoretical yield is determined by______.

Answer 23

Limiting reactant (mole ပမာဏနည်းတဲ့reactant)

Question 24

How do we find empirical formula?

Answer 24

1.Find the moles of the atom
2.Ratio cha
3.Divide by smallest no

Question 25

How do we find molecular number ?

Answer 25

Molar mass of molecular formula =x*molar mass of empirical formula

Question 26

Temperature is equal to _______ of the particles.

Answer 26

Average kinetic energy

Question 27

Water of crystallization

Answer 27

Compound that contain a fixed ratio of water molecule eg.CuSO4.5H2O

Question 28

The product that obtained after removing water of crystallization from its compound is

Answer 28

Anhydrous salts

Question 29

relation of cm3 & dm3

Answer 29

1dm3=1000cm3 1cm3=10^-3dm3

Question 30

Relation of m3 & dm3

Answer 30

1m3=1000dm3 1dm3=10^-3m3

Question 31

1L=

Answer 31

1L=1dm3=1000cm3