Answer:
a. 7.52
b. 16.5
c. 85
d. 6.03
Explanation:
significant number exempts 0 as a number which explains the last one. The two significant numbers there are 6 and 3
Answer:
What happens when electrons in atoms absorb or release energy? When electrons absorb or release energy, their electrons can move to higher or lower energy levels. These electrons lose energy by emitting light when they return to lower energy levels.
Explanation:
i really hope this helps
Answer:
Coefficient of 
Coefficient of
=8
Explanation:
We are given that a reaction in which
reacts with 
We have to find the coefficient of each reactants in balanced reaction

Coefficient is defined the constant value multiplied with a reactant in a reaction.
Coefficient of
=3
Coefficient of 
Coefficient of 
Coefficient of 
Coefficient of 
Coefficient of KOH=2
Hence, Coefficient of
and coefficient of 
Answer:
1.635 M
Explanation:
Given:
10 mL of 20 volumes Hydrogen Peroxide
Here,
20 volumes of Hydrogen Peroxide means that on decomposition of 1 mL of H₂O₂ 20 mL of O₂ is obtained
also,
means 1 dm³ of H₂O₂ solution produces 20 dm³ oxygen
Now,
at 298K and 1 atm
20 dm³ oxygen =
moles
or
= 0.817 moles
also,
2H₂O₂ → 2H₂O + O₂
thus,
1 dm³ of solution must contain 2 × moles of O₂ as moles of H₂O₂
thus,
Number of moles of H₂O₂ = 2 × 0.817
or
Number of moles of H₂O₂ = 1.635 moles
Hence,
For 20 volume hydrogen peroxide is 1.635 M