Answer : The change in internal energy is, 900 Joules.
Solution : Given,
Heat given to the system = +1400 J
Work done by the system = -500 J
Change in internal energy is equal to the sum of heat energy and work done.
Formula used :
where,
= change in internal energy
q = heat energy
w = work done
As per question, heat is added to the system that means, q is positive and work done by the system that means, w is negative.
Now put all the given values in the above formula, we get
Therefore, the change in internal energy is 900 J.
The change in internal energy depends on the heat energy and work done. As we will change in the heat energy and work done, then changes will occur in the internal energy. Hence, the energy is conserved.
D:
When electrons are gained, the charge of the atom decreases.
When you are given an atom with a charge, the oxidation of that atom is the charge. So by going from a Cr^3+ (Oxidation Number = 3) to a Cr^2+ (Oxidation Number = 2), the Oxidation Number thus decreases.
Answer:
Explanation:
Electrovalent is a word often associated with chemical bonding in the field of chemistry. It is special type of bond that occurs between metals and non-metals.
These bond types are interatomic interactions occurring between two atoms to ensure that they attain stable configurations.
- This bond type is also known as ionic bonds.
- It occurs between two species with a large electronegative diffference i.e one specie is electropositive and the other highly electronegative.
- The more electropositive specie is metal and it readily loses its valence electrons.
- The electronegative non-metal gains the electrons and becomes negatively charged.
- The electrostatic attraction between the metal and non-metals yields the electrovalent bonds.
I believe it the temperature of the air
Answer:
Q = 25.6 j
Explanation:
Given data:
Energy needed= ?
Mass of lead = 10.0 g
Initial temperature = 30 °C
Final temperature = 50°C
Cp = 0.128 j/g.°C
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 50°C - 30°C
ΔT = 20°C
Now we will put the values in formula.
Q = 10 g × 0.128 j/g.°C × 20°C
Q = 25.6 j
