<span>Answer: an element and a compound.
An element is a pure substance formed by one kind of atoms (element).
A compound is a pure substance formed by several types of atoms(elements) that are connected by chemical bonds.
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Description: The standard enthalpy of reaction is the enthalpy change that occurs in a system when matter is transformed by a given chemical reaction, when all reactants and products are in their standard states.
Answer: 498.51mmHg
Explanation:
First let us analyse what was given from the question:
T1 = 425K
T2 = 275.15K
P1 = 770 mmHg
P2 =?
Using the general gas equation
P1V1/T1 = P2V2/T2
But we were told from the question that the volume is constant. So, our equation becomes:
P1/T1 = P2/T2
770/425 = P2 /275.15
Cross multiply to express in linear form:
P2 x 425 = 770 x 275.15
Divide both side by 425, we have:
P2 = (770 x 275.15) /425
P2 = 498.51mmHg
Answer:
C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O
Explanation:
Let's start by counting how many molecules we have on each side.
<u>Reactants</u>
C - 5
H - 12
O - 2
<u>Products</u>
C - 1
O - 3
H - 2
We have to balance both sides. Since we have 5 carbon atoms on the reactants side and 1 carbon atom on the products side, we'll start with that. Write 5 as the coefficient for CO₂ to balance the carbons.
C₅H₁₂ + O₂ → 5CO₂ + H₂O
Now that the carbons are balanced, let's look at the hydrogens. There's 12 on the reactants side and 2 on the products side. To balance the hydrogens, we have to write 6 as the coefficient for H₂O.
C₅H₁₂ + O₂ → 5CO₂ + 6H₂O
Now the hydrogens are balanced. All that's left to do is balance the oxygens. Let's start by counting how many atoms we have on each side.
<u>Reactants</u>
C - 5
H - 12
O - 2
<u>Products</u>
C - 5
H - 12
O - 16
So, to balance the number of atoms on both sides, write 8 as the coefficient for O₂.
C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O
Lastly, let's check to make sure everything is balanced.
<u>Reactants </u>
C - 5
H - 12
O - 16
<u>Products</u>
C - 5
O - 16
H - 12
Both sides are balanced. Therefore, the balanced chemical equation is: C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O.
Hope that helps.