Answer: 253.8
Explanation:
The molar mass of iodine is 126.904. Multiply that by two and you get approximately 253.8 grams in two moles.
According to Avogadro's Law, same volume of any gas at standard temperature and pressure will occupy same volume. And one mole of any Ideal gas occupies 22.4 dm³ (1 dm³ = 1 L).
Data Given:
n = moles = ?
V = Volume = 16.8 L
Solution:
As 22.4 L volume is occupied by one mole of gas then the 16.8 L of this gas will contain....
= ( 1 mole × 16.8 L) ÷ 22.4 L
= 0.75 moles
Result:
16.8 L of Nitrogen gas will contain 0.75 moles at standard temperature and pressure.
Answer;
The above statement is true
upon heating a copper sample will expand, leading to a lower density
Explanation;
-The density of solids decreased with increase in temperature and vice versa. The increase in temperature causes the volume of the solid to increase which as a result decreases the density as Density=Mass/Volume. The temperature of a body is the average kinetic energy of the molecules present in it.
In other words; The temperature of a body is the average kinetic energy of the molecules present in it. Therefore; when heat is supplied ( or temperature is increased) the average kinetic energy increases which increases the volume and thus density decreases.
Answer:
The amount of heat required to raise the temperature of a 32g sample of water from 8°C to 22°C is 1,874.432 J
Explanation:
Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.
Sensible heat is the amount of heat that a body absorbs or releases without any changes in its physical state (phase change).
Between heat and temperature there is a direct proportional relationship. The constant of proportionality depends on the substance that constitutes the body and its mass, and is the product of the specific heat and the mass of the body. So, the equation that allows to calculate heat exchanges is:
Q = c * m * ΔT
where Q is the heat exchanged by a body of mass m, constituted by a substance of specific heat c and where ΔT is the variation in temperature.
In this case:
- c= 4.184
- m= 32 g
- ΔT= Tfinal - Tinitial= 22°C - 8°C= 14°C
Replacing:
Q= 32 g* 4.184 *14 °C
Solving:
Q= 1,874.432 J
<u><em>The amount of heat required to raise the temperature of a 32g sample of water from 8°C to 22°C is 1,874.432 J</em></u>
Answer:
B. Excited state
Explanation:
Energy levels higher than the ground state are called the excited states. This concept is based on the premise that electrons can move round the nucleus in certain permissibe orbits or energy levels.
The ground state is the lowest energy state available to the electron. This is usually the most stable state.
The excited state is any level higher than the ground state. An electron in an energy level has a definite amount of energy associated with it at that level.
