Avogadro's law states that under similar condition of T and P, equal number of particles. Experiments show that at one atmosphere pressure and at a temperature 273 K (i.e. at STP) one mole of any gas occupy a volume approximately 22.4 litre. Therefore number of moles of any sample of gas can be found by comparing its volume at STP with 22.4. 1 mole of any species contains `6.023xx10^(23)` particles which is denoted by symbol `N_(A)`. Number of atoms present in 1 gm-atom of an element or number of molecules present in 1 gm-molecule of any substance is equal to `N_(A)`. Hence it is number of particles present in one mole of the substance.
If `N_(AV)` is Avogardo's number, then 10 amu will be equal to _________ gram.

Options

A. `10 N_(AV)`
B. `(N_(AV))/(10)`
C. `(10)/(N_(AV))`
D. `N_(AV)`

Answer

To solve the question "If \( N_A \) is Avogadro's number, then 10 amu will be equal to _________ grams," we will follow these steps:

### Step 1: Understand the definition of 1 amu
1 amu (atomic mass unit) is defined as \( \frac{1}{12} \) of the mass of a carbon-12 atom. This means that the mass of 1 amu can be expressed in grams as:
\[ 1 \text{ amu} = \frac{1}{12} \times \text{mass of carbon-12 in grams} \]
Since the mass of 1 mole of carbon-12 is 12 grams, we can write:
\[ 1 \text{ amu} = \frac{12 \text{ grams}}{N_A} \]
where \( N_A \) is Avogadro's number, approximately \( 6.022 \times 10^{23} \) particles/mole.

### Step 2: Calculate the mass of 10 amu
To find the mass of 10 amu, we multiply the mass of 1 amu by 10:
\[ 10 \text{ amu} = 10 \times \left(\frac{12 \text{ grams}}{N_A}\right) = \frac{10 \times 12 \text{ grams}}{N_A} \]
This simplifies to:
\[ 10 \text{ amu} = \frac{120 \text{ grams}}{N_A} \]

### Final Answer
Thus, 10 amu is equal to:
\[ \frac{120}{N_A} \text{ grams} \]