Answer:
The square root of the molar mass of B ÷ the square root of the molar mass of A
Explanation:
Graham’s Law applies to the effusion of gases:
The rate of effusion (r) of a gas is inversely proportional to the square root of its molar mass (M).
If you have two gases A and B, the ratio of their rates of effusion is

Answer: The correct answer is a) Acetylcholine.
Explanation:
The acetylcholine is a very important neurotransmitter involved in the mediation of synaptic activity between neurons. Among its most important functions we find: expression of mood states, vasodilation, gastrointestinal motility, bronchoconstriction, circular iris muscle contraction and sweat gland secretion.
Therefore the correct answer is a) Acetylcholine.
Explanation:tr
a) Molar mass of HF = 20 g/mol
Atomic mass of hydrogen = 1 g/mol
Atomic mass of fluorine = 19 g/mol
Percentage of an element in a compound:

Percentage of fluorine:

Percentage of hydrogen:

b) Mass of hydrogen in 50 grams of HF sample.
Moles of HF = 
1 mole of HF has 1 mole of hydrogen atom.
Then 2.5 moles of HF will have:
of hydrogen atom.
Mass of 2.5 moles of hydrogen atom:
1 g/mol × 2.5 mol = 2.5 g
2.5 grams of hydrogen would be present in a 50 g sample of this compound.
c) As we solved in part (a) that HF molecules has 5% of hydrogen by mass.
Then mass of hydrogen in 50 grams of HF compound we will have :
5% of 50 grams of HF = 
An open system is
when there is a transfer of energy and matter with its surroundings.
A closed system is
where there is a transfer of energy, may it be heat or work, but not matter
with its surroundings.
An isolated system
is where there is no transfer of energy or matter with its surroundings.
Answer:
9.
a. NH2CH2COOH
b. The function group is what I put in bold.
c. carboxylic acid and amine
10.
a. NH2CH(CH3)COOH
b. The functional group is in bold.
c. carboxylic acid and amine
Explanation:
NH2 is amine (amino acid)
COOH is the carboxylic acid (acetic acid)