This is a D. combustion reaction
That is because you add O2 which is necessary for a combustion, while the results are CO2 and water. What you are missing is a ---> after the 2O2 (g)
Neutron, neutral subatomic particle that is a constituent of every atomic nucleus except ordinary hydrogen. It has no electric charge and a rest mass equal to 1.67493 × 10−27 kg—marginally greater than that of the proton but nearly 1,839 times greater than that of the electron.
Answer:
A. endothermic.
A. Yes, absorbed.
Explanation:
Let's consider the following thermochemical equation.
2 HgO(s) ⇒ 2 Hg(l) + O₂(g) ΔH = 182 kJ
The enthalpy of the reaction is positive (ΔH > 0), which means that the reaction is endothermic.
182 kJ are absorbed when 2 moles of HgO react (molar mass 216.59 g/mol). The heat absorbed when 72.8 g of HgO react is:

Answer:
b
Explanation:
b/c proton + neutron=mass number and
mass number - proton= neutron
The mass of magnesium, which has a density of 1.74 g/cm is 504.6 g.
<h3>What is mass?</h3>
Mass is the quantity of matter. Mass can be calculated by multiplying density by volume.
Magnesium is a chemical element with the atomic number 12. It is needed in the body in trace amounts. It can cause malnutrition in the body.
Mass = Density x volume
We know the density and the volume of magnesium.
Density = 1.74
Volume = 290
Density x volume
Putting the value in the equation
1.74 x 290 = 504.6 g
Thus, the mass of magnesium is 504.6 g.
To learn more about mass, refer to the below link:
brainly.com/question/22795877
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