Answer:
Moles of BCl₃ needed = 0.089 mol
Explanation:
Given data:
Moles of BCl₃ needed = ?
Mass of HCl produced = 10.0 g
Solution:
Chemical equation:
BCl₃ + 3H₂O → 3HCl + B(OH)₃
Number of moles of HCl:
Number of moles = mass/molar mass
Number of moles = 10.0 g/ 36.46 g/mol
Number of moles = 0.27 mol
Now we will compare the moles of HCl with BCl₃.
HCl : BCl₃
3 : 1
0.27 : 1/3×0.27 = 0.089 mol
Answer:


Explanation:
<u>Calculation of the mass of chromium as:-
</u>
Moles = 1.002 moles
Molar mass of chromium = 51.9961 g/mol
The formula for the calculation of moles is shown below:
Thus,

<u>Calculation of the mass of neon as:-
</u>
Moles =
moles
Molar mass of neon = 20.1797 g/mol
Thus,

Answer:
The true statement is option A.
Explanation:
Using ideal gas equation:
PV = nRT
where,
P = Pressure of gas = 1 atm
V = Volume of gas = ?
n = number of moles of gas = 1 mol
R = Gas constant = 0.0821 L.atm/mol.K
T = Temperature of gas = 273.15 K

V = 22.42 L
This means that 1 mole of an ideal gas at STP occupies 22.42 liters of volume.
So, 1 mole of helium gas and 1 mole of oxygen gas will have same value of volume in their respective balloons at STP.
Answer:
PV=nRT
n = PV/RT
n = m/Mm
m/Mm = PV/RT
m = MmPV/RT
T in kelvin = T Celsius + 273.15 = 293.15 K
m = (26.04 x 1.39 x 55)/(0.08206 x 293.15)
mass in grams = 82.8 grams
Explanation:
Ideal gases formula is PV=nRT, where:
P is the pressure (1.39 atm in this case)
V is the volume (55.0 L in this case)
R is the gas constant (0.08206 L.atm/K.mole)
T is the temperature (20.0C) should be converted to Kelvin
all the unit should correspond to the one in the R.
we also know that to find the mass, we can use number mole with the formula number of mole(n) = mass (m) divided by the molar mass (Mm). therefore we substituted that in the formula and make (m) the subject of the formula.
we found the mass to be 82.8 grams
Answer:
The density of O₂ gas is 1.71 
Explanation:
Density is a quantity that allows you to measure the amount of mass in a given volume of a substance. So density is defined as the quotient between the mass of a body and the volume it occupies:

An ideal gas is characterized by three state variables: absolute pressure (P), volume (V), and absolute temperature (T). The relationship between them constitutes the ideal gas law, an equation that relates the three variables if the amount of substance, number of moles n, remains constant and where R is the molar constant of the gases:
P * V = n * R * T
So, you can get:

The relationship between number of moles and mass is:

Replacing:


So:

Knowing that 1 mol of O has 16 g, the molar mass of O₂ gas is 32
.
Then:

In this case you know:
- P=1.27 atm
- molar mass of O₂= 32
.
- R= 0.0821

- T= 16 °C= 289 °K (0°C= 273°K)
Replacing:

Solving:
density= 1.71 
<u><em>The density of O₂ gas is 1.71 </em></u>
<u><em></em></u>