This law was proposed by Dalton in 1803 . According to this law , if two elements combune to form more than one compounds ,the masses of one element that combine with a fixed mass of the other element, are in the ratio of small whole number.
For exemple, hydrogen combines with oxygen to form two compounds ,namely, water and hydrogen peroxide.
Here, the masses of oxygen (i.e, 16g and 32g) which combine with a fixed mass of hydrogen (2g) bear a simple raio, i.e, 16 :32 or 1 :2 .
`N_(2)` and `O_(2)` combine to form a number of compounds such as `NO,N_(2)O,N_(2)O_(3),N_(2)O_(5)`. Show that these follow the law of multiple proportion.

Answer

To demonstrate that the compounds formed by nitrogen and oxygen (NO, N2O, N2O3, N2O5) follow the law of multiple proportions, we will analyze the mass ratios of nitrogen and oxygen in these compounds.

### Step 1: Identify the compounds and their molecular formulas
The compounds we are considering are:
1. NO
2. N2O
3. N2O3
4. N2O5

### Step 2: Calculate the molar masses of nitrogen and oxygen
- The molar mass of nitrogen (N) = 14 g/mol
- The molar mass of oxygen (O) = 16 g/mol

### Step 3: Determine the mass of oxygen in each compound
1. For NO:
- Mass of N = 14 g
- Mass of O = 16 g
2. For N2O:
- Mass of N = 2 × 14 g = 28 g
- Mass of O = 16 g
3. For N2O3:
- Mass of N = 2 × 14 g = 28 g
- Mass of O = 3 × 16 g = 48 g
4. For N2O5:
- Mass of N = 2 × 14 g = 28 g
- Mass of O = 5 × 16 g = 80 g

### Step 4: Establish ratios of masses of oxygen combining with a fixed mass of nitrogen
- For the first two compounds (NO and N2O), we will fix the mass of oxygen:
- Mass of O in NO = 16 g
- Mass of O in N2O = 16 g
- Ratio of O in NO to N2O = 16 g : 16 g = 1 : 1

- For the next two compounds (N2O3 and N2O5), we will fix the mass of nitrogen:
- Mass of N = 28 g (fixed)
- Mass of O in N2O3 = 48 g
- Mass of O in N2O5 = 80 g
- Ratio of O in N2O3 to N2O5 = 48 g : 80 g = 3 : 5 (after simplification)

### Step 5: Conclusion
From the calculations:
- The ratio of the masses of oxygen that combine with a fixed mass of nitrogen (28 g) in N2O3 and N2O5 is 3:5, which is a simple whole number.
- Therefore, we can conclude that the compounds NO, N2O, N2O3, and N2O5 follow the law of multiple proportions.