Pi x r2 is the equation to find circumference of a circle, pi x r^2 is the equation for finding the area of a circle.
<h3>
Answer:</h3>
Empirical formula is CrO
<h3>
Explanation:</h3>
<u>We are given;</u>
- Mass of sample of Chromium as 7.337 gram
- Mass of the metal oxide formed as 9.595 g
We are required to determine the empirical formula of the metal oxide.
<h3>Step 1 ; Determine the mass of oxygen used </h3>
Mass of oxygen = Mass of the metal oxide - mass of the metal
= 9.595 g - 7.337 g
= 2.258 g
<h3>Step 2: Determine the moles of chromium and oxygen</h3>
Moles of chromium metal
Molar mass of chromium = 51.996 g/mol
Moles of Chromium = 7.337 g ÷ 51.996 g/mol
= 0.141 moles
Moles of oxygen
Molar mass of oxygen = 16.0 g/mol
Moles of Oxygen = 2.258 g ÷ 16.0 g/mol
= 0.141 moles
<h3>Step 3: Determine the simplest mole number ratio of Chromium to Oxygen</h3>
Mole ratio of Chromium to Oxygen
Cr : O
0.141 mol : 0.141 mol
1 : 1
Empirical formula is the simplest whole number ratio of elements in a compound.
Thus the empirical formula of the metal oxide is CrO
Answer:
Mass = 0.008 g
Explanation:
Given data:
Volume of H₂ = 107 mL
Pressure = 104.8 KPa
Temperature = 30°C
Mass of H₂ present = ?
Solution:
Formula:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
Now we will convert the units of temperature, pressure and volume.
Temperature = 30+273 = 303 K
Volume of H₂ = 107 mL (107/1000= 0.107 L)
Pressure = 104.8 KPa (104.8/101 = 1.04 atm)
by putting values,
1.04 atm ×0.107 L = n× 0.0821 atm.L/ mol.K × 303 K
0.11 atm.L = n×24.87 atm.L/ mol
n = 0.11 atm.L / 24.87 atm.L/ mol
n = 0.004
Mass of H₂:
Mass = number of moles × molar mass
Mass = 0.004 mol × 2 g/mol
Mass = 0.008 g
I am pretty sure it's true. I hope it is