Can you be more specific?
...Diamond is the best conductor of heat, but heat also transmits readily through many other substances. Do you have multiple choice?
Answer:
burning wood be a chemical change because it wouldn’t be able to go back to its original form. A physical change would be a broken pencil. The pencil is still a pencil, it’s just a physical change.But if it were burned it would be a chemical change.
Explanation:
The given question is incomplete. The complete question is as follows.
A solution contains an unknown mass of dissolved barium ions. When sodium sulfate is added to the solution, a white precipitate forms. The precipitate is filtered and dried and then found to have a mass of 212 mg. What mass of barium was in the original solution? (Assume that all of the barium was precipitated out of solution by the reaction.)
Explanation:
When
and
are added then white precipitate forms. And, reaction equation for this is as follows.
It is given that mass (m) is 212 mg or 0.212 g (as 1 g = 1000 mg). Molecular weight of
is 233.43.
Now, we will calculate the number of moles as follows.
No. of moles = mass × M.W
= 
= 0.00091 mol of
Hence, it means that 0.00091 mol of
. Now, we will calculate the mass as follows.
Mass = moles × MW
=
= 0.124 grams or 124 mg of barium
Thus, we can conclude that mass of barium into the original solution is 124 mg.
Answer:

Explanation:
The question is asking, "At what temperature does the vapour pressure of water equal 3.4 atm?"
To answer this question, we can use the Clausius-Clapeyron equation:

Data:
p₁ = 1 atm; T₁ = 373.15C
p₂ = 3.4atm; T₂ = ?
R = 8.314 J·K⁻¹mol⁻¹

(The enthalpy of vaporization changes with temperature. Your value may differ from the one I chose.)
Calculation:

