Amount of HCl that would react with 5.0 g of manganese dioxide, as per the
given reaction will be:
4HCl(aq) + MnO2(s) ➡ 2H2O(l) + MnCl2(aq) + Cl2(2)
1. 4.8 g
2. 6.4 g
3. 2.8 g
4. 8.4 g
List I | List II | ||
a. | Micro | i. | m |
b. | Mega | ii. | m |
c. | Giga | iii. | m |
d. | Femto | iv. | m |
a | b | c | d | |
1. | i | iv | iii | ii |
2. | iii | iv | ii | i |
3. | ii | iii | iv | i |
4. | i | iii | iv | ii |
The numbers 234,000 and 6.0012 can be represented in scientific notation as:
1.
2. 0.234 and
3.
4. 2.34 and 6.0012
The number of significant figures in the numbers 5005, 500.0, and 126,000 are, respectively:
1. | 2, 4, and 3 | 2. | 4, 1, and 3 |
3. | 4, 4, and 6 | 4. | 4, 4, and 3 |
0.50 mol Na2CO3 and 0.50 M Na2CO3 are different because:
1. | Both have different amounts of Na2CO3. |
2. | 0.50 mol is the number of moles and 0.50 M is the molarity. |
3. | 0.50 mol Na2CO3 will generate more ions. |
4. | None of the above. |
Round up the following number into three significant figures:
i. 10.4107 ii. 0.04597 respectively are
1. | 10.4, 0.0460 | 2. | 10.41, 0.046 |
3. | 10.0, 0.04 | 4. | 10.4, 0.0467 |
The following data was obtained when dinitrogen and dioxygen react together to form different compounds:
Mass of dinitrogen | Mass of dioxygen | |
i. | 14 g | 16 g |
ii. | 14 g | 32 g |
iii. | 28 g | 32 g |
iv. | 28 g | 80 g |
The law of chemical combination applicable to the above experimental data is:
1. Law of reciprocal proportions
2. Law of multiple proportions
3. Law of constant composition
4. None of these.
The mass of CaCO3 required to react completely with 25 mL of 0.75 M HCl according to the given reaction would be:
CaCO3(s) + HCl(aq) ➡ CaCl2(aq) + CO2(g) + H2O(l)
1. 0.36 g
2. 0.09 g
3. 0.96 g
4. 0.66 g
Burning a small sample of welding gas (constituted of C and H only) in oxygen gives 3.38 g carbon dioxide, 0.690 g of water, and no other products. A volume of 10.0 L (measured at STP) of this welding gas is found to weigh 11.6 g. Molecular formula of welding gas would be:
1. C2H2
2. C2H6
3. CH
4. C2H4
The highest number of atoms is present in -
1. 52 moles of Ar
2. 52 u of He
3. 52 g of He.
4. All of the above have the same number of atoms