Answer: The mass in 
atoms of zinc is 0.405 g.
Explanation:
Given: Atoms of zinc =
It is known that 1 mole of every substance contains 
atoms. So, the number of moles in given number of atoms is as follows.
As moles is the mass of a substance divided by its molar mass. So, mass of zinc (molar mass = 65.39 g/mol) is calculated as follows.
Thus, we can conclude that the mass in atoms of zinc is 0.405 g.
Answer:
130,000 cubic centimeters
Explanation:
The volume of a box is its length multiplied by its width multiplied by its height (lwh). 423 times 12 times 25 is 126,900. When multiplying, the number of significant figures is the same as the number with the least number of significant figures. The correct number of significant figures in this example is 2, so 126,900 would need to round up to 130,000 in order to have 2 significant figures.
1 CH4 (g) + 2 O2 (g) -----> CO2 (g) + 2H2O(l) ΔH= - 890 kJ
1 mol 2 mol
1) If ΔH has minus, it means "release". We need only "release" choices.<span>
2) From reaction
1 mol </span>CH4 (g) "releases" ΔH= - 890 kJ - We do not have this choice.
2 mol O2 (g) "release" ΔH= - 890 kJ, so
1 mol O2 (g) "release" ΔH= - 445 kJ
Correct answer is B.
Trisulfer-dodecacarbonide
(maybe)
