The thermochemical equation is the chemical equation including the net change of enthalpy (heat).
The chemical equation for the decomposition of methanol to form methane and oxygen is:
2CH3OH --> 2CH4 + O2
The thermochemical equation is:
2CH3OH ---> 2CH4 + O2 - 252.8 kJ
Note that the heat is placed as negative at the right side because it is absorbed during the decomposition, so the environment will have 252.8 kJ less per each mole of O2 produced.
You can equivalently write:
2CH3OH + 252.8 kJ --> 2CH4 + O2
The chemical formula for methane is CH4
Ionic bonding would be the answer because they transfer electrons. This gives them a charge. If it loses electrons, it becomes an cation, with a positive charge. While if they gain an electron, they get a negative charge, and become a anion. Transferring an electron is losing or gaining, therefore your answer would be that since electrons are permanently being transferred, the answer is IONIC BOND.
Covalent bonds is a wrong answer because they share electrons, which gives them no charge (neutral).
Also, metallic bonding is not the correct answer.
So our final answer: A- Ionic bond
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.
Red blood cells is correct
