Answer:
The correct answer to this question is C
Explanation:
The balanced equation for the decomposition of solid lead iv oxide is as follows: 2PbO2 = 2PbO + O2.
Lead IV oxide decompose to give lead ll oxide and oxygen. Lead iv oxide is thermally unstable and it usually decomposes into oxygen and lead ll oxide when heated. Lead ll oxide is more stable than lead lV oxide.
Answer:
c) No, because Celsius is not an absolute temperature scale
Explanation:
converting 5 oC to kelvin which is the absolute temperature scale gives = 273 + 5 = 278 K
and converting 20 oC to kelvin = 20 + 273 = 293 K
the ratio = 278 / 293 = 0.94 approx 1 not 4
Answer : The concentration of A after 80 min is, 0.100 M
Explanation :
Half-life = 20 min
First we have to calculate the rate constant, we use the formula :



Expression for rate law for first order kinetics is given by:

where,
k = rate constant = 
t = time passed by the sample = 80 min
a = initial amount of the reactant = 1.6 M
a - x = amount left after decay process = ?
Now put all the given values in above equation, we get


Therefore, the concentration of A after 80 min is, 0.100 M
Answer:
= 0.28M
Explanation:
data:
volume = 0.250 L
= 0.250dm^3 ( 1litre = 1dm^3)
moles = 0.70 moles
Solution:
molarity = 
= 0.70 / 0.250
molarity = 0.28 M