Answer: Thats false the Russians were the first
Explanation:
Answer: a) The concentration after 8.8min is 0.17 M
b) Time taken for the concentration of cyclopropane to decrease from 0.25M to 0.15M is 687 seconds.
Explanation:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) concentration after 8.8 min:



b) for concentration to decrease from 0.25M to 0.15M


Answer:
pH= 3.82
Explanation:
Sodium ethanoate or sodium acetate (CH3COONa) ionises completely.
Ethanoic acid or acetic acid (CH3COOH), ionises partially because it is a weak acid.
Answer:
False
Explanation:
The urine is produced in the kidneys, each one of the kidneys is connected to a ureter. The ureter is a tube that propels the excreted urine to the urinary bladder. The urinary bladder is a deposit for the urine, here is collected and stored before disposal. After the urinary bladder, the urine goes through the urethra, which is a tube, to exit the body.
The answer is 64.907 amu.
The atomic mass of an element is the average of the atomic masses of its isotopes. The relative abundance of isotopes must be taken into consideration, therefore:
atomic mass of copper = atomic mass of isotope 1 * abundance 1 + atomic mass of isotope 2 * abundance 2
We know:
atomic mass of copper = 63.546 amu
The atomic mass of isotope 1 is: 62.939 amu
The abundance of isotope 1 is: 69.17% = 0.6917
The atomic mass of isotope 1 is: x
The abundance of isotope 2: 100% - 69.17% = 30.83% = 0.3083
Thus:
63.546 amu = 62.939 amu * 0.6917 + x * 0.3083
63.546 <span>amu = 43.535 amu + 0.3083x
</span>⇒ 63.546 amu - 43.535 amu = 0.3083x
⇒ 20.011 amu = 0.3083x
⇒ x = 20.011 amu ÷ 0.3083 = 64.907 amu