Atomic Mass and Atomic Mass Unit

Q. Differentiate between molecular mass and formula unit mass.
[2 Marks]

Q. 1 u or 1 amu (atomic mass unit) is equal to ___.

1. $\left(\frac{1}{16}\right)$${}^{\text{th}}$ of the mass of an atom of oxygen.
2. $\left(\frac{1}{12}\right)$${}^{\text{th}}$ of the mass of one atom of carbon 12.
3. 12 carbon atoms.
4. 16 oxygen atoms.

Q.

The atomic mass of Oxygen is 16 u.

Considering the above statement, which among the following options can be inferred?

1. The mass is with respect to Carbon -12 atom.

2. The atomic mass of hydrogen is 16 times the mass of Hydrogen.

3. The atomic mass of Oxygen is 16 of the mass of carbon 12 atom.

4. The mass is with respect to Carbon -12 atom and the atomic mass of Oxygen is 16 of the mass of carbon 12 atom.

Q.

What does the abbreviation amu stand for?

1. Atomic molecular unit

2. Atomic mass unit

3. Atomic mole unit

4. Atomic measuring unit

Q.

The number of molecules in 16.0g of oxygen is

1. $6.02\times {10}^{23}$
2. $6.02\times {10}^{-23}$
3. $3.01\times {10}^{-23}$
4. $3.01\times {10}^{23}$

Q.

One atomic mass unit is _______ of the mass of one atom of _________ isotope.

1. , Hydrogen

2. , Carbon-14

3. , Carbon-12

4. , Sulphur

Q.

The mass of Sodium in 11.7 g of Sodium chloride is

1. 2.3 g
2. 5.02 g
3. 6.9 g
4. 7.1 g

Q.

1 u or 1 amu means

1. $\frac{1}{12}$th mass of an atom of C-12 atom

2. Mass of Hydrogen molecule

3. Mass of C-12 atom

4. Mass of O-16 atom

Q.

Find the mass of oxygen contained in 1 kg of Potassium nitrate (KNO₃)

1. 475.5 g

2. 485.5 g

3. 475.2 g

4. 485.2 g

Q. One atomic mass unit is exactly equal to __________ of the mass of one atom of carbon-12.

1. 1/10
2. 1/12
3. 1/8
4. 1/14