Answer:
A catalyst is a chemical substance that alters the rate of chemical reaction not consumed by the reaction. Hence, a catalyst can be recovered chen unchanged at the ends of chemical reaction. Catalyst can be divided into two typ the basis whether it speeds up or slowdowns the rate of chemical reaction. The positive catalyst and negative catalyst.
Answer:
2 CrO42- + 3N2O + 10 H+ -----> 2Cr3+ + 6NO + 5H2O
Explanation:
2 CrO42- + 3N2O + 10 H+ -----> 2Cr3+ + 6NO + 5H2O
Oxidizing agent: -----------------------------> CrO42-
Reducing agent: ----------------------------> N2O
explanation:
in CrO4-2 oxdiation state of Cr = +6
in Cr+3 oxidation state = +3
+6 oxidation state changed from +3 it is reduction .
so CrO4-2 is oxidizing agent
atomatically
N2O should be reducing agent
<u>Answer:</u> The uncertainty in the velocity of oxygen molecule is 
<u>Explanation:</u>
The diameter of the molecule will be equal to the uncertainty in position.
The equation representing Heisenberg's uncertainty principle follows:

where,
= uncertainty in position = d = 
= uncertainty in momentum = 
m = mass of oxygen molecule = 
h = Planck's constant = 
Putting values in above equation, we get:

Hence, the uncertainty in the velocity of oxygen molecule is 
The answer to this question would be: 3.125%
Half-life is the time needed for a radioactive molecule to decay half of its mass. In this case, the strontium-89 is already gone past 5 half lives. Then, the percentage of the mass left after 5 half-lives should be:
100%*(1/2^5)= 100%/32=3..125%