Atoms of the same element with different mass numbers are called isotopes
Answer : The correct option is, 
Explanation :
- Oxidation reaction : It is defined as the reaction in which a substance looses its electrons. That means, the loss of electrons takes place.
Or we can say that, oxidation reaction occurs when a reactant losses electrons in the reaction.
- Reduction reaction : It is defined as the reaction in which a substance gains electrons. That means, the gain of electrons takes place.
Or we can say that, reduction reaction occurs when a reactant gains electrons in the reaction.
According to the electrochemical series,
most likely to be reduced because
Hence, the ion most likely to be reduced is
.
C. A magnet causing a metal object to move
Answer: Light, Thermal, Kinetic
Explanation:
The lamp converts the electric energy to light energy.
The toaster converts the electric energy to thermal energy.
The fan converts the electric energy to kinetic energy.
Good luck with your test!
Answer : The correct option is, (C) 1.7
Explanation :
First we have to calculate the moles of
and
.


The balanced chemical reaction will be:

0.01 mole of
dissociate to give 0.01 mole of
ion and 0.02 mole of
ion
and
0.03 mole of
dissociate to give 0.03 mole of
ion and 0.03 mole of
ion
That means,
0.02 moles of
ion neutralize by 0.02 moles of
ion.
The excess moles of
ion = 0.03 - 0.02 = 0.01 mole
Total volume of solution = 100 + 300 = 400 ml = 0.4 L
Now we have to calculate the concentration of
ion.


Now we have to calculate the pH of the solution.
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)


Therefore, the pH of the solution is, 1.7