<u>Answer:</u> The concentration of
comes out to be 0.16 M.
<u>Explanation:</u>
To calculate the concentration of acid, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is NaOH.
We are given:

Putting values in above equation, we get:

Hence, the concentration of
comes out to be 0.1862 M.
Answer:
2Fe + O₂ -------------------> 2FeO
8 mol Fe produce
8 mol Fe * 2 mol FeO / 2 mol Fe = 8 mol FeO
Mass of FeO = 8 mol FeO * 71.85 g/mol = 574.8 grams FeO
Explanation:
Having 8 mol of Iron means 8 moles of iron oxide can be produced. Each mole of iron oxide has a molecular weight of 71.85 grams. Therefore, 8 moles of iron oxide should weight 574.8 grams.
A) Na + H20 ----> NaOH + H2
B) 2Na + 2H20 ----> 2NaOH + H2
Follow exact same process as your other questions I have answered.
Hey There!
No, this would be considered a chemical change. :)