Answer:- B:
is the right answer.
Solution:- The balanced equation is:

We have been given with 8.75 grams of oxygen and asked to calculate the grams of hydrogen needed to react with given grams of oxygen according to the balanced equation.
From balanced equation, 1 mole of oxygen reacts with 2 moles of hydrogen.
So, let's convert grams of oxygen to moles and multiply it by the mole ratio to calculate the moles of hydrogen that are easily converted to grams on multiplying by it's molar mass.
The complete set up looks as:

= 
Hence, the right option is B:
.
Answer:
773.51495 grams
Explanation:
1 moles KBr to grams = 119.0023 grams
6.5*119.0023 = 773.51495 grams
Answer:
c. precipitation
Explanation:
Let's consider the following balanced net ionic equation.
Cl⁻(aq) + AgNO₃(ag) ⇒ AgCl(s) + NO₃⁻ (ag)
What kind of reaction is this?
a. acid-base. No, because the reactants are not acids and bases.
b. redox. No, because all the species have the same oxidation numbers in the reactants and the products
c. precipitation. Yes, because an insoluble compound (AgCl) is produced, which then precipitates.