Answer:
3.02e23
Explanation:
carbon molecular weight = 12 g /mol
1 mol = 6.02e23 atoms
your sample, 6 g / 12 g/mol = 0.5 mol
0.5 x 6.02e23 =
Answer:
answer A
Explanation:
A) the quantity of usable energy declines with each transformation → True . Since the entropy increases , the amount of energy that can not be converted to useful energy increases and since the total amount of energy is conserved, the quantity of useful energy decreases.
B) energy can be neither created nor destroyed → False in the context of entropy , since the energy is conserved regardless of the changes in entropy (First law → conservation of energy vs second law → increase of entropy)
C) life should be impossible → False . Since the second law states that the entropy of the <u>universe </u>increases with time . Then the system (life) can experience a decrease in entropy at the expense of a larger increase in entropy of the surroundings ( so the net increase is positive)
D) it is not possible to observe an increase in molecular organisation → False . Same as C. A system can experience a decrease in entropy at the expense of a larger increase in entropy of the surroundings ( so the net increase is positive)
Answer:
The answer to your question is 100.8 g
Explanation:
Data
mass of Barium chloride = 90 g
mass of Barium sulfate = ?
Balanced chemical reaction
BaCl₂ + H₂SO₄ ⇒ BaSO₄ + 2HCl
Process
1.- Calculate the molar mass of BaCl₂ and BaSO₄
BaCl₂ = 137.3 + (2 x 35.5) = 208.3g
BaSO₄ = 137.3 + 32 + (16 x 4) = 233.3g
2.- Use proportions to find the mass of BaSO₄
208.3 g of BaCl₂ --------------------- 233.3 g of BaSO₄
90 g of BaCl₂ --------------------- x
x = (90 x 233.3) / 208.3
x = 20997/ 208.3
x = 100.8 g
3.- Conclusion
There will be produced 100.8 g of BaSO₄
The rate constant : k = 9.2 x 10⁻³ s⁻¹
The half life : t1/2 = 75.3 s
<h3>Further explanation</h3>
Given
Reaction 45% complete in 65 s
Required
The rate constant and the half life
Solution
For first order ln[A]=−kt+ln[A]o
45% complete, 55% remains
A = 0.55
Ao = 1
Input the value :
ln A = -kt + ln Ao
ln 0.55 = -k.65 + ln 1
-0.598=-k.65
k = 9.2 x 10⁻³ s⁻¹
The half life :
t1/2 = (ln 2) / k
t1/2 = 0.693 : 9.2 x 10⁻³
t1/2 = 75.3 s
Although the moon's distance from earth varies each month because of its eccentric orbit, the moon's mean distance from Earth is nonetheless increasing at the rate of about 3.8 centimeters (1.5 inches) per year
