# Chemical Arithmetic Test 3

Total Questions:50 Total Time: 60 Min

Remaining:

## Questions 1 of 50

Question:Which of the following elements of matter would best convey that there is life on earth

Oxygen

Hydrogen

Carbon

Iron

## Questions 2 of 50

Question:The compound which is added to table salt for maintaining proper health is

KCl

$$KBr$$

$$NaI$$

$$MgB{r_2}$$

## Questions 3 of 50

Question:Which of the following contains only one element

Marble

Diamond

Glass

Sand

## Questions 4 of 50

Question:In known elements, the maximum number is of

Metals

Non-metals

Metalloids

None of these

## Questions 5 of 50

Question:The number of significant figures in 60.0001 is

5

6

3

2

## Questions 6 of 50

Question:A sample was weighted using two different balances. The resultâ€™s were (i) 3.929 g (ii) 4.0 g. How would the weight of the sample be reported

3.929 g

3 g

3.9 g

3.93 g

## Questions 7 of 50

Question:Which of the following pairs of substances illustrate the law of multiple proportions

CO and $$C{O_{\rm{2}}}$$

$${H_2}O{\rm{ and }}{D_2}O$$

$$NaCl{\rm{ and }}NaBr$$

$$MgO{\rm{ and }}Mg{(OH)_2}$$

## Questions 8 of 50

Question:1.0 g of an oxide of A contained 0.5 g of A. 4.0 g of another oxide of A contained 1.6 g of A. The data indicate the law of

Reciprocal proportions

Constant proportions

Conservation of energy

Multiple proportions

## Questions 9 of 50

Question:In compound A, 1.00 g nitrogen unites with 0.57 g oxygen. In compound B, 2.00 g nitrogen combines with 2.24 g oxygen. In compound C, 3.00 g nitrogen combines with 5.11 g oxygen. These results obey the following law

Law of constant proportion

Law of multiple proportion

Law of reciprocal proportion

Dalton's law of partial pressure

## Questions 10 of 50

Question:Hydrogen combines with oxygen to form $${H_2}O$$ in which 16 g of oxygen combine with 2 g of hydrogen. Hydrogen also combines with carbon to form $$C{H_4}$$ in which 2 g of hydrogen combine with 6 g of carbon. If carbon and oxygen combine together then they will do show in the ratio of

6 : 16 or 12 : 32

06:18

01:02

12:24

## Questions 11 of 50

Question:2 g of hydrogen combine with 16 g of oxygen to form water and with 6 g of carbon to form methane. In carbon dioxide 12 g of carbon are combined with 32 g of oxygen. These figures illustrate the law of

Multiple proportions

Constant proportions

Reciprocal proportions

Conservation of mass

## Questions 12 of 50

Question:An element forms two oxides containing respectively 53.33 and 36.36 percent of oxygen. These figures illustrate the law of

Conservation of mass

Constant proportions

Reciprocal proportions

Multiple proportions

## Questions 13 of 50

Question:For preparing 0.1 N solution of a compound from its impure sample of which the percentage purity is known, the weight of the substance required will be

More than the theoretical weight

Less than the theoretical weight

Same as the theoretical weight

None of these

## Questions 14 of 50

Question:1 mol of $$C{H_4}$$contains

$$6.02 \times {10^{23}}$$atoms of H

4 g atom of Hydrogen

$$1.81 \times {10^{23}}$$molecules of $$C{H_4}$$

3.0 g of carbon

## Questions 15 of 50

Question:In the reaction $$2N{a_2}{S_2}{O_3} + {I_2} \to N{a_2}{S_4}{O_6} + 2NaI$$, the equivalent weight of $$N{a_2}{S_2}{O_3}$$(mol. wt. = M) is equal to

M

$$M/2$$

$$M/3$$

$$M/4$$

## Questions 16 of 50

Question:When potassium permanganate is titrated against ferrous ammonium sulphate, the equivalent weight of potassium permanganate is

Molecular weight /10

Molecular weight /5

Molecular weight /2

Molecular weight

## Questions 17 of 50

Question:The mass of a molecule of water is

$$3 \times {10^{ - 26}}$$kg

$$3 \times {10^{ - 25}}$$kg

$$1.5 \times {10^{ - 26}}$$kg

$$2.5 \times {10^{ - 26}}$$kg

## Questions 18 of 50

Question:1.24 gm P is present in 2.2 gm

$${P_4}{S_3}$$

$${P_2}{S_2}$$

$$P{S_2}$$

$${P_2}{S_4}$$

## Questions 19 of 50

Question:The atomic weights of two elements A and B are 40 and 80 respectively. If x g of A contains y atoms, how many atoms are present in 2x g of B

$$\frac{y}{2}$$

$$\frac{y}{4}$$

y

2y

## Questions 20 of 50

Question:Assuming fully decomposed, the volume of $$C{O_2}$$released at STP on heating 9.85g of $$BaC{O_3}$$(Atomic mass of Ba=137) will be

0.84 L

2.24 L

4.06 L

1.12 L

## Questions 21 of 50

Question:What volume of $$N{H_3}$$gas at STP would be needed to prepare 100ml of 2.5 molal (2.5m) ammonium hydroxide solution

0.056 litres

0.56 litres

5.6 litres

11.2 litres

## Questions 22 of 50

Question:If the density of water is 1 g $$c{m^{ - 3}}$$then the volume occupied by one molecule of water is approximately

$$18\,\,c{m^3}$$

$$22400\,\,c{m^3}$$

$$6.02 \times {10^{ - 23}}\,\,c{m^3}$$

$$3.0 \times {10^{ - 23}}\,\,c{m^3}$$

## Questions 23 of 50

Question:Caffeine has a molecular weight of 194. If it contains 28.9% by mass of nitrogen, number of atoms of nitrogen in one molecule of caffeine is

4

6

2

3

## Questions 24 of 50

Question:A 400 mg iron capsule contains 100 mg of ferrous fumarate, $${(CHCOO)_2}Fe$$. The percentage of iron pasent in it is approximately

33%

25%

14%

8%

## Questions 25 of 50

Question:The number of moles of oxygen in $$1\;L$$ of air containing 21% oxygen by volume, in standard conditions, is

0.186 mol

0.21 mol

2.10 mol

0.0093 mol

## Questions 26 of 50

Question:The number of molecules in $$8.96\;L$$ of a gas at $${0^o}C$$ and 1 atmosphere pressure is approximately

$$6.02 \times {10^{23}}$$

$$12.04 \times {10^{23}}$$

$$18.06 \times {10^{23}}$$

$$24.08 \times {10^{22}}$$

## Questions 27 of 50

Question:The equivalent weight of a metal is 9 and vapour density of its chloride is 59.25. The atomic weight of metal is

23.9

27.3

36.3

48.3

## Questions 28 of 50

Question:The molecular weight of a gas is 45. Its density at STP is

22.4

11.2

5.7

2

## Questions 29 of 50

Question:The total number of protons in 10 g of calcium carbonate is ($${N_0} = 6.023 \times {10^{23}}$$)

$$1.5057 \times {10^{24}}$$

$$2.0478 \times {10^{24}}$$

$$3.0115 \times {10^{24}}$$

$$4.0956 \times {10^{24}}$$

## Questions 30 of 50

Question:The number of molecules in 16 g of methane is

$$3.0 \times {10^{23}}$$

$$6.02 \times {10^{23}}$$

$$\frac{{16}}{{6.02}} \times {10^{23}}$$

$$\frac{{16}}{{3.0}} \times {10^{23}}$$

## Questions 31 of 50

Question:Number of molecules in 100 ml of each of $${O_2},\,N{H_3}{\rm{ and}}\,C{O_2}$$at STP are

In the order $$C{O_2} < {O_2} < N{H_3}$$

In the order $$N{H_3} < {O_2} < C{O_2}$$

The same

$$N{H_3} = C{O_2} < {O_2}$$

## Questions 32 of 50

Question:The molecular weight of hydrogen peroxide is 34. What is the unit of molecular weight

$$g$$

$$mol$$

$$g\,mo{l^{ - 1}}$$

$$mol\,{g^{ - 1}}$$

## Questions 33 of 50

Question:A sample of phosphorus trichloride $$(PC{l_3})$$ contains 1.4 moles of the substance. How many atoms are there in the sample

4

5.6

$$8.431 \times {10^{23}}$$

$$3.372 \times {10^{24}}$$

$$2.409 \times {10^{24}}$$

## Questions 34 of 50

Question:The number of sodium atoms in 2 moles of sodium ferrocyanide is

$$12 \times {10^{23}}$$

$$26 \times {10^{23}}$$

$$34 \times {10^{23}}$$

$$48 \times {10^{23}}$$

## Questions 35 of 50

Question:The percentage of oxygen in $$NaOH$$ is

40

60

8

10

## Questions 36 of 50

Question:The percentage of nitrogen in urea is about

46

85

18

28

## Questions 37 of 50

Question:The percentage of $${P_2}{O_5}$$in diammonium hydrogen phosphate $${(N{H_4})_2}HP{O_4}$$is

23.48

46.96

53.78

71

## Questions 38 of 50

Question:If $$1\frac{1}{2}$$moles of oxygen combine with Al to form $$A{l_2}{O_3}$$the weight of Al used in the reaction is (Al=27)

27 g

54 g

49.5 g

31 g

## Questions 39 of 50

Question:The percentage of Se in peroxidase anhydrous enzyme is 0.5% by weight (atomic weight=78.4). Then minimum molecular weight of peroxidase anhydrous enzyme is

$$1.568 \times {10^4}$$

$$1.568 \times {10^3}$$

$$15.68$$

$$3.136 \times {10^4}$$

## Questions 40 of 50

Question:$${H_2}$$ evolved at STP on complete reaction of 27 g of Aluminium with excess of aqueous $$NaOH$$ would be

22.4

44.8

67.2

33.6 litres

## Questions 41 of 50

Question:To neutralise 20 ml of $$M/10$$ sodium hydroxide, the volume of $$M/20$$ hydrochloric acid required is

10 ml

15 ml

20 ml

40 ml

## Questions 42 of 50

Question:Hydrochloric acid solutions A and B have concentration of 0.5 N and 0.1 N respectively. The volume of solutions A and B required to make 2 litres of 0.2 N hydrochloric are

0.5 l of A + 1.5 l of B

1.5 l of A + 0.5 l of B

1.0 l of A + 1.0 l of B

0.75 l of A + 1.25 l of B

## Questions 43 of 50

Question:5 ml of N HCl, 20 ml of $$N/2\,\,{H_2}S{O_4}$$ and 30 ml of $$N/3\,\,HN{O_3}$$ are mixed together and volume made to one litre. The normality of the resulting solution is

$$N/5$$

$$N/10$$

$$N/20$$

$$N/40$$

## Questions 44 of 50

Question:Under similar conditions of pressure and temperature, 40 ml of slightly moist hydrogen chloride gas is mixed with 20 ml of ammonia gas, the final volume of gas at the same temperature and pressure will be

100 ml

20 ml

40 ml

60 ml

## Questions 45 of 50

Question:Number of moles of $$KMn{O_4}$$required to oxidize one mole of $$Fe({C_2}{O_4})$$in acidic medium is

0.6

0.17

0.2

0.4

## Questions 46 of 50

Question:A hydrocarbon contains 86% carbon, 488ml of the hydrocarbon weight 1.68 g at STP. Then the hydrocarbon is an

Alkane

Alkene

Alkyne

Arene

## Questions 47 of 50

Question:The ratio of amounts of $${H_2}S$$needed to precipitate all the metal ions from 100 ml of 1 M $$AgN{O_3}$$and 100 ml of 1 M $$CuS{O_4}$$will be

01:01

01:02

02:01

None of these

## Questions 48 of 50

Question:How many grams of caustic potash required to completely neutralise 12.6 gm $$HN{O_3}$$

22.4 KOH

1.01 KOH

6.02 KOH

11.2 KOH

## Questions 49 of 50

Question:$$1.5$$ mol of $${O_2}$$ combine with $$Mg$$ to form oxide $$MgO$$. The mass of $$Mg$$ (at. mass 24) that has combined is

$$72\;g$$

$$36\;g$$

$$48\;g$$

$$24\;g$$

## Questions 50 of 50

Question:100 g $${\rm{CaC}}{{\rm{O}}_{\rm{3}}}$$ reacts with 1litre 1 N HCl. On completion of reaction how much weight of $$C{O_2}$$ will be obtain

$$5.5\;g$$
$$11\;g$$
$$22\;g$$
$$33\;g$$
$$44\;g$$