Answer:
79 g
Explanation:
Density (d) of iron = 7.9 g/cm³
Volume of the iron (V) = 10 cm³
Mass of the iron (m) = ?
Solution:
Formula will be used
d = m/V
As we have to find mass so rearrange the above equation
m = dV . . . . . . . . . . . (1)
Put values in above equation 1
m = 7.9 g/cm³ x 10cm³
m = 79 g
So,
mass of iron = 79 g
Step 1:
Divide mass of each element with its M.mass in order to find out moles.
C = 63.2 g / 12 g/mol = Moles = 5.26 moles
H = 5.26 g / 1.008 g/mol = Moles = 5.21 moles
C = 41.6 g / 16 g/mol = Moles = 2.6 moles
Step 2:
Select moles of the element with least value and divide all moles of element by it,
C H O
5.26/2.6 : 5.21/2.6 : 2.6/2.6
2.02 : 2.00 : 1
Result:
Empirical Formula = C₂H₂O
Answer:
2.5 moles of KOOH are produced.
Explanation:
1)Given data:
Number of moles of KOOH produced = ?
Number of moles of LiClO = 5 mol
Solution:
Chemical equation:
2LiClO + KHSO₄ → Li₂SO₄ + Cl₂ + KOOH
now we will compare the moles of KOOH and LiClO.
LiClO : KOOH
2 : 1
5 : 1/2×5 = 2.5
2.5 moles of KOOH are produced.
Answer:
The second option
Explanation:
I took the quiz and got it correct
ANSWER
EXPLANATION
Given that
The energy released by the system is 12.4J
Work done on the surrounding is 4.2J
Follow the steps below to find the change in energy
In the given data, energy is said to be released to the surroundings
Recall, that exothermic reaction is a type of reaction in which heat is released to the surroundings. Hence, change in enthalpy is negative
Step 1; Write the formula for calculating change in energy
Since heat is released to the surrounding, then q = -12J
Recall, that work done by the system on the surroundings is always negative
Hence, w = -4.2J
Step 2; Substitute the given data into the formula in step 1
Therefore, the change i
