Answer:
0.0498 mol
Explanation:
Number of moles = concentration in mol/L × volume in L
Concentration = 1 M = 1 mol/L
Volume = 49.8 mL = 49.8/1000 = 0.0498 L
Number of moles = 1×0.0498 = 0.0498 mol
Answer:
49.2 g/mol
Explanation:
Let's first take account of what we have and convert them into the correct units.
Volume= 236 mL x (
) = .236 L
Pressure= 740 mm Hg x (
)= 0.97 atm
Temperature= 22C + 273= 295 K
mass= 0.443 g
Molar mass is in grams per mole, or MM=
or MM=
. They're all the same.
We have mass (0.443 g) we just need moles. We can find moles with the ideal gas constant PV=nRT. We want to solve for n, so we'll rearrange it to be
n=
, where R (constant)= 0.082 L atm mol-1 K-1
Let's plug in what we know.
n=
n= 0.009 mol
Let's look back at MM=
and plug in what we know.
MM= 
MM= 49.2 g/mol
Answer:
Hello - this is Mrs. Gussman, your chemistry teacher. I wrote this exam question and posting it online is a violation of the academic integrity policy. Remove this post immediately.
Explanation:
Answer:
2.24dm³
Explanation:
Given parameters:
Mass of He = 40g
Unknown:
Volume of Helium = ?
Solution:
To solve this problem, we convert the given mass to number of moles.
Number of moles =
molar mass of He = 4g/mol
Number of moles =
= 0.1mole
So;
1 mole of gas at rtp occupies a volume of 22.4dm³
0.1 mole of He will occupy a volume of 0.1 x 22.4 = 2.24dm³
Answer:
E. potassium (K) and bromine (Br)
Explanation:
An ionic bond is formed between compounds with a large electronegativity difference between them. It is usually between a metal and non-metal.
- Potassium is a true metal found in group 1 on the periodic table.
- Bromine is a highly electronegative non-metal which is a halogen.
- Potassium will lose one of its electrons which will be gained by the Bromine.
- The electrostatic attraction between the two species will cause the ionic bond to form.
- The ability of one specie willing to lose electron and the other gaining, is the main bed rock of ionic bonding.