How much neutrons, protons and electrons does hydride have

Neutrons = 0

Protons = 1

Electrons = 2

Explanation: The formula for hydride is H- it is an ion.

The number of protons is the atomic number of Hydrogen which is 1.

The number of neutrons can be calculated by subtracting the Atomic mass to its Atomic number

So 1 - 1 = 0

Since it is an ion, hydride gains 1 electron as indicated by its charge so the number of electrons is equal to 2.

the answer is 75.0%.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2