The answer for the following problem is described below.
<em><u> Therefore the standard enthalpy of combustion is -2800 kJ</u></em>
Explanation:
Given:
enthalpy of combustion of glucose(Δ
of 
) =-1275.0
enthalpy of combustion of oxygen(Δ of 
) = zero
enthalpy of combustion of carbon dioxide(Δ of 
) = -393.5
enthalpy of combustion of water(Δ of 
) = -285.8
To solve :
standard enthalpy of combustion
We know;
Δ = ∈Δ (products) - ∈Δ (reactants)
(s) +6 (g) → 6 (g)+ 6 (l)
Δ = [6 (-393.5) + 6(-285.8)] - [6 (0) + (-1275)]
Δ = [6 (-393.5) + 6(-285.8)] - [0 - 1275]
Δ = 6 (-393.5) + 6(-285.8) - 0 + 1275
Δ = -2361 - 1714 - 0 + 1275
Δ =-2800 kJ
<em><u> Therefore the standard enthalpy of combustion is -2800 kJ</u></em>
Answer:
The percentage of the block contains 15% after 60 years.
Explanation:
Step 1: Formula for half-life time
To calculate the half-life time we will use the following formula:
At = A0 * 1/2 ^(x/t)
With At = the quantity after a time t
A0 = The quantity at time t = 0 (start)
x = time in this case = 60 years
t= half-life time = 22 years
Step 2: Calculate the percentage after 60 years
In this case: after 60 years the percentage will be
A0= 10 * 1/2 ^(60/22)
A0 = 1.5
A0 / At = 1.5 /10 = 0.15
0.15 *100% = 15 %
The percentage of the block contains 15% after 60 years.
Answer:
Catalysts help in increasing rates of reactions
Both containers have the same number of molecules= 5.62 x 10²³
<h3>Further explanation</h3>
Given
22.4 L of hydrogen gas
22.4 L of oxygen gas
25°C and 1 atm.
Required
true statement
Solution
Conditions at T 25 ° C and P 1 atm are stated by RTP (Room Temperature and Pressure). Vm in this condition = 24 liters / mol
and from Avogadro's Law :
<em>At the same temperature and pressure, the ratio of gas volume will be equal to the ratio of gas moles </em>
So two gas have the same molecules
1 mol = 6.02 x 10²³ molecules
24 L = 1 mol, so for 22.4 L :
Taking into account the reaction stoichiometry, 2 moles of CaO are required to react with 2 moles of Ca(OH)₂.
<h3>Reaction stoichiometry</h3>
In first place, the balanced reaction is:
CaO + H₂O → Ca(OH)₂
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
- CaO: 1 mole
- H₂O: 1 mole
- Ca(OH)₂: 1 mole
<h3>Moles of CaO required</h3>
The following rule of three can be applied: If by stoichiometric reaction 1 mole of Ca(OH)₂ is produced by 1 mole of CaO, 2 moles of Ca(OH)₂ are produced by how many moles of CaO?
moles of CaO= 2 moles
Finally, 2 moles of CaO are required to react with 2 moles of Ca(OH)₂.
Learn more about the reaction stoichiometry:
brainly.com/question/24741074
brainly.com/question/24653699
#SPJ1
