Answer:
168.812 g/mol
Explanation:
atomic mass. of Be= 9.012
atomic mass of Br= 79.90
because there is a 2 after Br you double the atomic mass
79.90(2)= 159.8
To find the molar mass add the atomic masses of each element
9.012+159.8=168.812
Answer:
Mass = 16.4 g
Explanation:
Given data:
Mass of K = 8.50 g
Mass of KCl produced = ?
Solution:
Chemical equation:
2K + Cl₂ → 2KCl
Number of moles of K:
Number of moles = mass/ molar mass
Number of moles = 8.50 g/ 39 g/mol
Number of moles = 0.22 mol
Now we will compare the moles of potassium and potassium chloride.
K : KCl
2 : 2
0.22 : 0.22
Mass of KCl:
Mass = number of moles × molar mass
Mass = 0.22 mol × 74.55 g/mol
Mass = 16.4 g
Astronauts brought back 500 lb of rock samples from the moon. How many kilograms did they bring back? (1 kg = 2.20 lb)
A. 500 kg
B. 1,100 kg
C. 498 kg
D. 227 kg
I believe it is D.
THE SUBSTANCE PRESENT AT THE START OF THE REACTION ARE CALLED REACTANT
Answer:
P₂ = 1.05 atm
Explanation:
Given data:
Initial temperature = 24.0 °C (24+273 = 297 K)
Initial pressure = 0.900 atm
Final pressure = ?
Final temperature = 75 °C (75 + 273 =348 K)
Volume = constant
Solution:
According to Gay-Lussac Law,
The pressure of given amount of a gas is directly proportional to its temperature at constant volume and number of moles.
Mathematical relationship:
P₁/T₁ = P₂/T₂
Now we will put the values in formula:
0.900 atm / 297 K = P₂/348 K
P₂ = 0.900 atm × 348 K / 297 K
P₂ = 313.2 atm. K /297 K
P₂ = 1.05 atm
