Consider the following changes. H2O(g) → H2O(s)
H2O2(l) → H2O2(g)
H2(g) + F2(g) → 2 HF(g)
2 C4H10(g) + 13 O2(g) → 8 CO2(g) + 10 H2O(l)
Mg3P2(s) + 6 H2O(l) → 3 Mg(OH)2(s) + 2 PH3(g)
(a)
At constant temperature and pressure, in which of these changes is work done by the system on the surroundings? (Select all that apply.)
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(b)
In which of these changes is work done by the surroundings on the system? (Select all that apply.)
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(c)
In which of these changes is no work done? (Select all that apply.)
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These questions are based on the attached photo. the experiment is about burning magnesium metal with oxygen. 1. write the balanced chemical equation for the reaction you are performing. 2. calculate the mass of magnesium metal used in each trial. o trial 1: o trial 2: 3. calculate the actual yield of magnesium oxide for each trial. o trial 1: o trial 2: 4. magnesium is the limiting reactant in this experiment. calculate the theoretical yield of mgo for each trial. o trial 1: o trial 2: 5. determine the percent yield of mgo for your experiment for each trial. o trial 1: o trial 2: 6. determine the average percent yield of mgo for the two trials. your company currently uses a process with a similar cost of materials that has an average percent yield of 91 percent. if the average percent yield of this process is higher than that, this could save the company money. what is your recommendation to the company? support your recommendation using your data, calculations, and understanding of stoichiometry gathered from this lab.

The biosphere of the earth is made up of what compound? organic or inorganic?

Anyone who's in connections academy chemistry b have the factors that affect the rate of a reaction portfolio already done?