Answer:
a. 3.72 [atm]
Explanation:
For a gas at constant temperature, (with no change in number of molecules of the gas), we can apply Boyle's Law: 
![(1.556[atm])(268.5[mL])=P_2(112.4[mL])](https://tex.z-dn.net/?f=%281.556%5Batm%5D%29%28268.5%5BmL%5D%29%3DP_2%28112.4%5BmL%5D%29)
![\dfrac{(1.556[atm])(268.5[mL\!\!\!\!\!\!\!\!{--}])}{112.4[mL \!\!\!\!\!\!\!\!{--}]}=\dfrac{P_2(112.4[mL]\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!{-----})}{112.4[mL]\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!{-----}}](https://tex.z-dn.net/?f=%5Cdfrac%7B%281.556%5Batm%5D%29%28268.5%5BmL%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%7B--%7D%5D%29%7D%7B112.4%5BmL%20%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%7B--%7D%5D%7D%3D%5Cdfrac%7BP_2%28112.4%5BmL%5D%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%7B-----%7D%29%7D%7B112.4%5BmL%5D%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%5C%21%7B-----%7D%7D)
![3.716957[atm]=P_2](https://tex.z-dn.net/?f=3.716957%5Batm%5D%3DP_2)
It seems like the answer should have 4 significant figures since all of the other quantities have 4 significant figures, but the closest answer choice of those provided is a. 3.72
Because each element has an exactly defined line emission spectrum, scientists are able to identify them by the color of flame they produce.
B. 1, 1, 1, 2
Explanation:
You only need to balance the NaNO3 on the right. Since there is 2 NO3 on the left, you need to put a 2 in front of the NaNO3 on the right. Everything else is already balanced so the only coefficient needed is 2 in front of the NaNO3.
Acid-base indicator changes color based on pH.
drop some in a solution n watch the color changes. different indicators show different colors at different pH. they usually have standard colors for comparison.
i believe the answer is...
Atoms of isotopes of an element have different numbers of protons.
