Answer:
The standard enthalpy of formation of HgO is -90.7 kJ/mol.
Explanation:
The reaction between Hg and oxygen is as follows.
From the given,
Molar mass of HgO = 216.59 g/mol
Mass of HgO decomposed = 18.5 g
Amount of heat absorbed = 7.75 kJ
From the reaction,
The standard enthalpy of formation = 
During the decomposition of 1 mol of HgO , 90.7 kJ of energy absorbed.
For the formation of 1 mol of HgO , 90.7 kJ of energy is release
Therefore, the enthalpy of formation of mercury(II)Oxide is -90.7 kJ/mol
Answer is b. Hope it help
Answer:
this is because spreading it makes more sunlight hit the cloth which results in it drying faster
Magnesium + Hydrocloric acid -> Magnesium chloride + hydrogen
You can observe a single displacement reaction
"Describe to show that the has formed is hydrogen"
I don't know what you mean. I can show the chemical equation though.
Mg(s) + 2 HCl(aq) --> MgCl 2(aq) + H 2(g)
The formula for force is F=ma. Because weight is a measure of force, then we can substitute the weight of the meteor, 3204 N, for F in the the equation for force. We also know that the acceleration of gravity on Earth is 9.8 m/s^2. To find the mass, simply divide both sides of the equation by the value of acceleration to get
Therefore, the value of the mass of the meteor is 326.9 kg.
