C. NO2 is covalent. Hope this helps!
Explanation:
I thought it was B, but i was wrong... TwT, so now you know not to choose that one, but i belive the right answer was D.
Answer:
0.108
Explanation:
You use the formula Q =mco
M is mass
Q is th heat release
C is specific heat
O is the temperature change
Substitute what you have and what you get in the information in the equation then you will get your answers
Answer:
It will take
to exhaust the supply
Explanation:
We have to apply unitary method to solve this problem.
Divide total petroleum reserve by petroleum consumption in each year to calculate estimated time.
Presently,
joules of petroleum are being consumed per year.
Hence, applying unitary method,
joules of petroleum can be consumed in 
Answer:
It will take 6.6 hours for 75% of the lead to decay.
Explanation:
The radioactive decay follows first order rate law
The half life and rate constant are related as

The rate law for first order reaction is
![time=\frac{1}{k}(ln[\frac{A_{0}}{A_{t}}]](https://tex.z-dn.net/?f=time%3D%5Cfrac%7B1%7D%7Bk%7D%28ln%5B%5Cfrac%7BA_%7B0%7D%7D%7BA_%7Bt%7D%7D%5D)
Where
A0 = initial concentration = 1 g
At= final concentration = 0.25 g (as 75% undergoes decay so 25% left]
