Answer:
you can use the idea of molecular masses to calculate easily
Explanation:
atomic mass
Really...i think it can also be atomic number..
If you only want to balance nuclear reactions, then you should know that number of nucleons are conserved before and after nuclear reaction. Also, charge is conserved as well.
Other things which are conserved in a nuclear reaction are:
Conservation of:
1. Parity
2. Spin
3. angular momentum(vector sum of intrinsic spin and orbital angular momentum)
4. linear momentum
5. Isotopic spin
6. Energy
Answer : The reaction is endothermic.
Explanation :
Formula used :
where,
= change in temperature = 
Q = heat involved in the dissolution of KCl = ?
m = mass = 0.500 + 50.0 = 50.5 g
c = specific heat of resulting solution = 
Now put all the given value in the above formula, we get:
The heat involved in the dissolution of KCl is positive that means as the change in temperature decreases then the reaction is endothermic and as the change in temperature increases then the reaction is exothermic.
Hence, the reaction is endothermic.
Answer:
- They are highly reactive metals
- They have low electro negativity
- They have low ionization energy
- They don't exist alone in nature
- They have low densities
Explanation:
Alkali metals are the elements in group 1 of the periodic table. They include Sodium, Lithium, Potassium e.t.c.
Due to the fact they have one atom in their outermost shell, they are very unstable because they easily react with other elements and are therefore don't exist alone in nature but combined with other elements for this same reason.
Since alkali metals don't easily attract other elements due to it's lone pair in the outer most shell, it can be said to have low electro negativity.
Also, they don't need energy to discharge their electrons since they are highly reactive due to their lone pair in the outermost shell and so we say they have low ionization energy.
Due to this reason, they also have low densities.
