The fomula is NH4 (1+)
There are only two elements N and H.
As per oxidation state rules, the most electronegative element will have a negative oxidation state and the other element will have a positive oxidation state.
N is more electronative than H, so H will have a positive oxidation state and nitrogen will have a negative oxidation state.
You can also use the rule that states the hydrogen mostly has 1+ oxidation state,except when it is bonded to metals.
In conclusion the oxidation state of H in NH4 (1+) is 1+.
Now you must know that the sum of the oxidations states equals the charge of the ion, which in this case is 1+.
That implies that 4* (1+) + x = 1+
=> x = (1+) - 4(+) = 3-
Answer: the oxidation state of N is 3-, that is the option b.
Answer:- 0.273 kg
Solution:- A double replacement reaction takes place. The balanced equation is:

We have 0.29 L of 22% m/v aluminum nitrate solution. m/s stands for mass by volume. 22% m/v aluminium nitrate solution means 22 g of it are present in 100 mL solution. With this information, we can calculate the grams of aluminum nitrate present in 0.29 L.

= 63.8 g aluminum nitrate
From balanced equation, there is 1:3 mol ratio between aluminum nitrate and sodium chlorate. We will convert grams of aluminum nitrate to moles and then on multiplying it by mol ratio we get the moles of sodium chlorate that could further be converted to grams.
We need molar masses for the calculations, Molar mass of sodium chlorate is 106.44 gram per mole and molar mass of aluminum nitrate is 212.99 gram per mole.

= 
sodium chlorate solution is 35% m/m. This means 35 g of sodium chlorate are present in 100 g solution. From here, we can calculate the mass of the solution that will contain 95.7 g of sodium chlorate and then the grams are converted to kg.

= 0.273 kg
So, 0.273 kg of 35% m/m sodium chlorate solution are required.
Answer:
Molecular mass is the amount of mass associated with a molecule. It is also called as molecular weight. It can be calculated by adding the mass of each atom multiplied by the number of atoms of the element present in the molecule. For example, water is made up of 2 hydrogen atoms and 1 oxygen atom.
Explanation:
Fe+CuSO4⟶Cu+FeSO4
Given that
FeSO4 = 92.50 g
Number of moles = amount in g / molar mass
=92.50 g / 151.908 g/mol
=0.609 moles FeSO4
Now calculate the moles of CuSO4 as follows:
0.609 moles FeSO4 * 1 mole CuSO4 /1 mole FeSO4
= 0.609 moles CuSO4
Amount in g = number of moles * molar mass
= 0.609 moles CuSO4 * 159.609 g/mol
= 97.19 g CuSO4