MgBr2(aq) is an ionic compound which will have the releasing of 2 Br⁻ ions ions in water for every molecule of MgBr2 that dissolves.
MgBr2(s) --> Mg+(aq) + 2 Br⁻(aq)
[Br⁻] = 0.065 mol MgBr2/1L × 2 mol Br⁻ / 1 mol MgBr2 = 0.13 M
The answer to this question is [Br⁻] = 0.13 M
Carbon dating has<span> given archeologists a more accurate method by which they </span>can<span> determine the age of ancient artifacts. The </span>halflife<span> of </span>carbon 14<span> is </span>5730<span> ± 30 </span>years<span>, and the method of dating lies in trying to determine how </span>much carbon 14<span> (</span><span>the radioactive isotope of carbon) is present in the artifact and comparing it to levels</span>
Answer:
b. The final state of the substance is a gas.
d. The sample is initially a liquid. One or more phase changes will occur.
Explanation:
Methane has the following properties:
- Normal melting point: 90.7 K
- Normal boiling point: 111.65 K
*"Normal" refers to normal pressure (1 atm).
According to this, we can affirm:
- Below 90.7 K, methane is solid.
- Between 90.7 K and 111.65 K, methane is liquid.
- Above 111.65 K, methane is gas.
<em>A sample of methane at a pressure of 1.00 atm and a temperature of 93.1 K is heated at constant pressure to a temperature of 158 K. Which of the following are true? Choose all that apply.</em>
<em>a. The liquid initially present will solidify.</em> FALSE. The liquid will vaporize.
<em>b. The final state of the substance is a gas.</em> TRUE.
<em>c. The sample is initially a solid.</em> FALSE. The sample is initially a liquid.
<em>d. The sample is initially a liquid. One or more phase changes will occur. </em>TRUE.
The gas inside the can and the can’s volume are both constant.
The gas pressure increases with increasing temperature.
The can will burst if the pressure becomes great enough.
The gas law that applies is Gay-Lussac’s law.
