Answer:
d and e - Sodium and antimony
Explanation:
The atomic numbers remain the same, while the mass numbers change (because neutrons are being added or taken away).
sodium has an atomic number of 19 and a mass number of 39 - in d, it has an atomic number of 19 but a mass number of 40. therefore, it is an isotope
antimony has an atomic number of 51 and a mass number of 121.60 - in e, it has an atomic number of 51, but a mass number of 123. therefore, it is an isotope
Because the water near the equator gets more direct sunlight.
Answer:
The concentration of methyl isonitrile will become 15% of the initial value after 10.31 hrs.
Explanation:
As the data the rate constant is not given in this description, However from observing the complete question the rate constant is given as a rate constant of 5.11x10-5s-1 at 472k .
Now the ratio of two concentrations is given as

Here C/C_0 is the ratio of concentration which is given as 15% or 0.15.
k is the rate constant which is given as 
So time t is given as

So the concentration will become 15% of the initial value after 10.31 hrs.
Answer:
A
Explanation:
this should be obvious if you read it haha
Answer:
The temperature is 30,92K
Explanation:
We use the formula PV=nRT. We convert the unit of pressure in kPa into atm.
101,325kPa----1atm
121kPa-------x=(121,3kPax 1 atm)/101,325kPa=1, 2 atm
PV=nRT---->T= (PV)/(RT)
T=(1,2 atm x 3L)/(1,42 mol x 0,082 l atm/K mol )= 30, 91721058 K