Answer:
hot, less, rise, top, cold, closer, more, sink
Explanation:
I'm in high-school done this long time ago
Answer:
Explanation:
The volume and amount of gas are constant, so we can use Gay-Lussac’s Law:
At constant volume, the pressure exerted by a gas is directly proportional to its temperature.
Data:
p₁ =5.7 atm; T₁ = 100.0 °C
p₂ = ?; T₂ = 20.0 °C
Calculations:
1. Convert the temperatures to kelvins
T₁ = (100.0 + 273.15) K = 373.15
T₂ = (20.0 + 273.15) K = 293.15
2. Calculate the new pressure
Stable isotopes are not radioactive nor dangerous.
Unstable isostopes are radioactive and have different mass of the element.
Answer:
2.04 x 10²⁴ molecules
Explanation:
Given parameters:
Mass of Be(OH)₂ = 145.5g
To calculate the number of molecules in this mass of Be(OH)₂ we follow the following steps:
>> Calculate the number of moles first using the formula below:
Number of moles = mass/molarmass
Since we have been given the mass, let us derive the molar mass of Be(OH)₂
Atomic mass of Be = 9g
O = 16g
H = 1g
Molar Mass = 9 + 2(16 + 1)
= 9 + 34
= 43g/mol
Number of moles = 145.5/43 = 3.38mol
>>> We know that a mole is the amount of substance that contains Avogadro’s number of particles. The particles can be atoms, molecules, particles etc. Therefore we use the expression below to determine the number of molecules in 3.38mol of Be(OH)₂:
Number of
molecules= number of moles x 6.02 x 10²³
Number of molecules= 3.38 x 6.02 x 10²³
= 20.37 x 10²³ molecules
= 2.04 x 10²⁴ molecules
