When magnesium chloride reacts with water, 5.85 l hcl(g) is produced.
molar mass of hcl = 36.5 g/mol
molar mass of mgcl2 = 95.2 g/mol

how many moles of hcl was produced?
how many moles of mgcl2 reacted?
what mass of mgcl2 reacted?

How many moles of HCl was produced?

⇒ 0.261 moles of HCl

How many moles of MgCl2 reacted?

⇒ 0.131 moles of MgCl2

What mass of MgCl2 reacted?

⇒ 12.4 g MgCl2

Explanation:

i just did it

(i) 0.261 moles of HCl, (ii) 0.131 moles of and (iii) 12.5 grams of

Explanation: The balanced equation for the formation of HCl by the reaction magnesium chloride with water is:

From above balanced equation, there is 1:2 mol ratio between magnesium chloride and HCl.

As per the given information, 5.85 L of HCl gas is produced. here, temperature and pressure is not mentioned, so let's assume STP conditions.

At STP, volume of 1 mol of a gas is 22.4 L. With the help of this, we can calculate the moles of HCl present in 5.85 L.

= 0.261 mol HCl

As there is 1:2 mol ratio between magnesium chloride and HCl, we can calculate the moles of magnesium chloride from the above calculated moles of HCl as:

= 0.131 mol

Molar mass of magnesium chloride is given as 95.2 gram per mol. On multiplying the moles by molar mass we can calculate its mass reacted.

= 12.5 g

it's c. elements are placed in rows based on how may valencies electrons have.

im not exactly sure but i think its b!