Answer:
The answer is an attached file
Explanation:
I hope it'll be useful to you.
Mass of X₂O₇ = 54,9g
2x + 33,6g = 54,9g
2x = 54,9g - 33,6g
2x = 21,3g | :2
x = 10,65g/mol
The answer is
<span>2PbS(s) + 3O2(g) = 2PbO(s) + 2SO2(g)
Your answer is not yet balanced because you have 3 oxygen atoms. it should be balanced by multiplying both side by 2 such as the balanced equation I made. To check it, I will explain why your answer is not yet balanced.
check: (from your equation)
</span> 1-Pb-1
1-S-1
2 -O-3
the difference between the reactant and the product of Oxygen will prove that it is not yet balanced.
If you use 2PbS(s) + 3O2(g) = 2PbO(s) + 2SO2(g), to check it:
2-Pb-2
2-S-2
6 -O-6
then this is now balance
Answer:
Yes
Explanation:
First remember that a significant figure are basically values that contribute to the precision of a value. In any scientific notation the values are significant figures because these values stay the same. In this case we have two significant figures which is 6 and 0, you can further prove that they are significant figures by converting the notation into standard form.

Negative so move the decimal point to the left:

6 and 0 are the significant figures in this standard notation because it's precise to it's actual value which is 6.0.
To sum up, the values you have on the left side of a notation are significant figures since they will not change no matter if it's standard or scientific notation meaning it's precise.
Hope this helps.
Answer:
400.197mmHg
Explanation:
P1V1 / T1 = P2V2 / T2
Where P1=524 mm Hg V1 =275 ml T1 = 35°C +273 = 308k
V2= 325-ml T2= 5°C+273 = 278k , P2= ?
Substituting the values into the formula.
524 mm Hg ×275 ml /308k = P2×325-ml/278k
Cross multiply
524 mm Hg ×275 ml×278k=308k×P2×325-ml
40059800= 100100×P2
P2 = 40059800/100100
P2= 400.197mmHg
Hence, the second pressure will be 400.197mmHg