The kind of thermochemical equation represented below
that is
CaO(s) + H2O (l) = Ca(OH)2 (s) +65.2 kj
is exothermic ( answer B)
This is because its heat energy has a + sign meaning that heat is released by the reaction above.
Iron(II) oxide also refers to a family of related non-stoichiometric compounds, which are typically iron deficient with compositions ranging from Fe0.84O to Fe0.95O.
Answer:
mass = 242.372 grams
Explanation:
1- getting the number of moles of HCl:
molarity = number of moles of solute / liters of solution
4 = number of moles of HCl / 5.2
number of moles of HCl = 4 * 5.2 = 20.8 moles
2- getting the number moles of magnesium:
From the balanced equation given, we can note that one mole of magnesium is required to react with two moles of HCl. To get the number of moles required to react with 20.8 moles of HCl. we will simply do cross multiplication as follows:
1 mole of Mg ...............> 2 moles of HCl
?? moles of Mg ...........> 20.8 moles of HCl
Number of moles of Mg = 20.8 / 2 = 10.4 moles
3- getting the mass of Mg:
number of moles = mass / molar mass
Using the periodic table, we can find that the molar mass of magnesium is 24.305 grams.
This means that:
10.4 = mass / 24.305
mass = 24.305 * 10.4
mass = 242.372 grams
Hope this helps :)
Answer:
Chemical change
Explanation:
There are types of changes in nature namely: physical change and chemical change. A physical change is a change that does not alter the chemical composition of the substances involved, hence, no new substances are formed. On the other hand, a chemical change changes the chemical composition of the involved substances to form new substances.
Based on the definition of the types of changes below, the equation depicted in this question is a CHEMICAL CHANGE because it involves a rearrangement of the atoms of each element in the reactants to produce new sets of products with a new chemical formula.
C17H17ON3(s) + 2C4H6O3(l) → C21H21O5N(s) + 2C2H4O2(l)