Answer: E. Occurs when methane gas is burned.
Explanation:
A chemical change occurs when matter undergoes a change to form a new substance with different chemical properties, and the reaction is usually not reversible.
In the case of burning methane gas (CH4) ,oxygen and methane are the reactants, while the new substance formed from the reaction are carbondioxide (CO2) and water (H2O) .
If that in the middle between the 10 and 24 is a caret, then I believe this is the work:
3.6 x 10^24 atoms Zn / 6.022x10^23 atom/mol Zn = 6 mol Zn
6 mol Zn x 65.36 g/mol Zn = 390 g Zn if you carry two significant figures with rounding at each step.
I believe that is correct as all the units cancel properly.
Answer:

Explanation:
The pressure is constant, so, to calculate the volume, we can use Charles' Law:
\dfrac{V_{1}}{T_{1}} = \dfrac{V_{2}}{T_{2}}
Data:
V₁ = ?; T₁ = 450 K
V₂ = 103.4 L; T₂ = 284.9 K
Calculation:

Answer:
by changing the number of protons in the atom
Explanation:
Elements are defined by their number of protons. For example, an element with 1 proton is hydrogen, and an element with 2 protons is helium. Changing the number of neutrons or electrons in a preexisting element will not make a new element. Is is possible to create new elements, but it requires large amounts of heat and/or pressure.
Answer:
D
Explanation:
According to the law of conservation of mass, matter can neither be created nor destroyed. The implication of this is that the total mass of reactants should be equal to the total mass of products.
There should be equal masses of reactants and products on both sides of the reaction equation. This most important condition is only satisfied by option D.