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Answer:
1.209g of MgO participates
Explanation:
In this problem, we have 0.030 moles of MgO that participates in a particular reaction.
And we are asked to solve for the mass of MgO that participates, that means, we need to convert moles to grams.
To convert moles to grams we need to use molar mass of the compound:
<em>1 atom of Mg has a molar mass of 24.3g/mol</em>
<em>1 atom of O has a molar mass of 16g/mol</em>
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That means molar mass of MgO is 24.3g/mol + 16g/mol = 40.3g/mol
And mass of 0.030 moles of MgO is:
0.030 moles MgO * (40.3g/mol) =
<h3>1.209g of MgO participates</h3>
Answer:
1552.83J Released
Explanation:
1. mass/m=225
Initial temp:86C, final:32.5C
Changed Temp: 32.5-86= -53.5C
s=0.129 J/gC
Formula: q= m times s times changed Temp.
q=(225)(0.129)(-53.5)
q= -1552.83 J
q=1552.83 J Released
Answer:
The answer is B
Explanation:
Less air means less air pressure. At a certain point, there is very little air pressure to push against the outward pressure of the helium inside the balloon. It will then expand until the rubber breaks, and the balloon bursts
<u>Answer:</u> The formation of given amount of oxygen gas results in the absorption of 713 kJ of heat.
<u>Explanation:</u>
To calculate the number of moles, we use the equation:

Given mass of oxygen gas = 83 g
Molar mass of oxygen gas = 32 g/mol
Putting values in above equation, we get:

For the given chemical equation:

<u>Sign convention of heat:</u>
When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.
By Stoichiometry of the reaction:
When 3 moles of oxygen gas is formed, the amount of heat absorbed is 824.2 kJ
So, when 2.594 moles of oxygen gas is formed, the amount of heat absorbed will be = 
Hence, the formation of given amount of oxygen gas results in the absorption of 713 kJ of heat.