Which coefficient correctly balance the equation cao + h2o -> ca(oh)2 -1; 2; 3 -1; 1; 1 -2; 1; 2 -1; 2; 1

For the equation that we are given:

→

We see that on the reactants side we have:

Ca: 1 mol

O: 2 mol

H: 2 mol

And then we see that on the products side we have:

Ca: 1 mol

O: 2 mol

H: 2 mol

Therefore since we have equal moles of each of the elements on both sides of the equation, this equation is balanced how it is.

So the correct coefficients for this equation are: B) 1, 1, 1.

the answer is barium and copper bromide

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