Answer:
Knowing that boron has an atomic mass of 10,811 means that all boron isotopes on average weigh 10,811 u.
Explanation:
The atomic mass of an atom is the mass of the atom measured in u (unified atomic mass unit), although we can also express it as Da (Dalton's unit)
Atomic mass refers to the average mass that all isotopes of that element have.
When we speak of isotopes we are referring to the element itself but with a different number of neutrons, which makes it modify its mass number.
Answer is:
7.8 lb of 21% aluminum and 33.2 ib of <span>
42% aluminum.</span>
ω₁<span> = 21% ÷ 100% = 0.21.
ω</span>₂<span> = 42% ÷ 100% = 0.42.
ω</span>₃<span> = 38% ÷ 100% = 0.38.
</span>m₁ = ?.
m₂<span> = ?.
</span>m₃ = m₁ + m₂<span>.
</span>m₃ = 41 pounds.
m₁ = 41 lb - m₂<span>.
ω</span>₁ · m₁ + ω₂ ·m₂ = ω₃ · m₃.
0.21 · (41 lb -
m₂) + 0.42 · m₂ = 0.38 · 41 lb.
8.61 lb - 0.21m₂ + 0.42m₂ = 15.58 lb.
0.21m₂ = 6.97 lb.
m₂ = 6.97 lb ÷ 0.21.
m₂ = 33.2 lb.
m₁ = 41 lb - 33.2 lb.
m₁<span> = 7.8 lb.</span>
Answer:
Final volumeof the gas = 2.84 L
Explanation:
The formular to be used here is the general gas equation. the formular is being used because it gives the relationship between the three gas parameters (volume, temperature and pressure) mentioned.
The general gas equation is given as;

where;
P1 = initial pressure
V1 = initial volume
T1 = initial temperature
P2 = Final pressure
V2 = Final volume
T2 = Final temperature
From the question,
P1 = 1.00 atm
P2 = 0.85atm
T1 = 25C + 273 = 298K (Converting to kelvin)
T2 = 15C + 273 = 288K (Converting to kelvin)
V1 = 2.5L
V2 = ?
from the equation, making V2 subject of formula we have;

V2 = (1*2.5*288)/(298*0.85) = 2.84 L.
Atomic number = 18 (Number of protons)
Mass number = 18 + 20 (Number of protons + neutrons)
If you’re talking about a reaction, an increase in the products (values on the right side of the chemical equation) would cause the reaction to shift left instead of right. Also a decrease in the reactants.
Also, could be wrong, but increasing the volume/ decreasing the pressure on the reactant side will cause the reaction to shift left