Answer: The closeness, arrangement and motion of the particles in a substance change when it changes state. Materials are a store of internal energy , due to the motion of particles and the chemical bonds between them. When a substance is heated, its internal energy increases: the movement of its particles increases.
Explanation:
Answer:
The answers are in the explanation.
Explanation:
The energy required to convert 10g of ice at -10°C to water vapor at 120°C is obtained per stages as follows:
Increasing temperature of ice from -10°C - 0°C:
Q = S*ΔT*m
Q is energy, S specific heat of ice = 2.06J/g°C, ΔT is change in temperature = 0°C - -10°C = 10°C and m is mass of ice = 10g
Q = 2.06J/g°C*10°C*10g
Q = 206J
Change from solid to liquid:
The heat of fusion of water is 333.55J/g. That means 1g of ice requires 333.55J to be converted in liquid. 10g requires:
Q = 333.55J/g*10g
Q = 3335.5J
Increasing temperature of liquid water from 0°C - 100°C:
Q = S*ΔT*m
Q is energy, S specific heat of ice = 4.18J/g°C, ΔT is change in temperature = 100°C - 0°C = 100°C and m is mass of water = 10g
Q = 4.18J/g°C*100°C*10g
Q = 4180J
Change from liquid to gas:
The heat of vaporization of water is 2260J/g. That means 1g of liquid water requires 2260J to be converted in gas. 10g requires:
Q = 2260J/g*10g
Q = 22600J
Increasing temperature of gas water from 100°C - 120°C:
Q = S*ΔT*m
Q is energy, S specific heat of gaseous water = 1.87J/g°C, ΔT is change in temperature = 20°C and m is mass of water = 10g
Q = 1.87J/g°C*20°C*10g
Q = 374J
Total Energy:
206J + 3335.5 J + 4180J + 22600J + 374J =
30695.5J =
30.7kJ
<span>The Kelvin scale is an absolute temperature scale, while the Celsius scale is not. When you convert a temperature from Celsius to Kelvin, you add 273 degrees to the temperature. However, when you calculate a temperature change, you get the same number, whether you use the Celsius or the Kelvin scale.</span>
The option that would best contrast the real and the model atoms is letter "D. model of an atom is not as small as an actual atom". The size of an atom is said to be no more than 0.1 to 0.5 nanometers. The models are used to proper illustrate the atom's physical attributes. That is why, it needs to be bigger in size.
Answer:
Nitrogen is limiting reactant while hydrogen is in excess.
Explanation:
Given data:
Mass of N₂ = 25 g
Mass of H₂ = 25 g
Mass of ammonia formed = ?
Solution:
Chemical equation:
N₂ + 3H₂ → 2NH₃
Number of moles of Nitrogen:
Number of moles = mass/ molar mass
Number of moles = 25 g/ 28 g/mol
Number of moles = 0.89 mol
Number of moles of hydrogen:
Number of moles = mass/ molar mass
Number of moles = 25 g/ 2 g/mol
Number of moles = 12.5 mol
Now we will compare the moles of both reactant with ammonia.
H₂ ; NH₃
3 : 2
12.5 : 2/3×12.5 = 8.3
N₂ ; NH₃
1 : 2
0.89 : 2×0.89 = 1.78
The number of moles of ammonia produced by nitrogen are less thus nitrogen is limiting reactant while hydrogen is in excess.
