wayground logo

Free Printable Worksheets

NEW

Font size

S
M
L
XL
Worksheets

Some basic concepts of chemistry

Total questions: 10

Worksheet time: 10mins

Name
Class
Date
1.

Which of the following statement is INCORRECT

a)

protium has no neutron

b)

C14 is used for finding age of old wooden objects

c)

Ca-40 and Ar-50 are isotopes

d)

Ca-40 and Ar -40 are isobars

2.

What will be the molarity of a solution, which contains 5.85 g of NaCl(s) per

500 mL?

a)

4

b)

20

c)

0.2

d)

2

3.

The number of atoms present in one mole of an element is equal to Avogadro

number. Which of the following element contains the greatest number of

atoms?

a)

4g He

b)

46g Na

c)

0.4g Ca

d)

12g He

4.

What is the mass percent of carbon in carbon dioxide?

a)

40

b)

27

c)

32

d)

10

5.

The empirical formula and molecular mass of a compound are CH2O and

180 g respectively. What will be the molecular formula of the compound?

a)

C2H4O2

b)

HCHO

c)

C6H12O6

d)

CH3COOH

6.

Which of the following reactions is not correct according to the law of

conservation of mass.

(i)

(ii)

(iii)

(iv)

a)

2Mg(s) + O2(g) --> 2MgO(s)

b)

C3H8(g) + O2(g) -->CO2(g) + H2O(g)

c)

P4(s) + 5O2(g)--> P4O10(s)

d)

CH4(g) + 2O2(g) --> CO2(g) + 2H2O (g)

7.

For aq sol, which is true

a)

1m=1M

b)

1m is less concentrated than 1M

c)

1m is more concentrated than 1M

d)

Data insufficient

8.

Which is used to Express amount of mercury vapour in atmosphere

a)

M

b)

m

c)

Mole fraction

d)

ppm

9.

What vol of air is needed for complete combustion of 32g methane

a)

2*22.4l

b)

4*22.4l

c)

20*22.4l

d)

22.4l

10.

If 20 litre nitrogen gas reacts with 30 litre hydrogen gas to give ammonia, the volume of product formed is

a)

40

b)

20

c)

50

d)

30