Answer:
1 = strontium
2 = technetium
3 = silver
Explanation:
Strontium is present in 2 group of periodic table. It is alkaline earth metal. It is most reactive element and can not found free in nature. it is insoluble in water but react with water and form strontium hydroxide and hydrogen gas is also produced. It is radioactive element.
It is similar to the calcium and can incorporated into bones. The food rich with strontium is used to avoid the osteoporosis. It is found in leafy vegetables, grains, sea foods etc.
In given series strontium is highest in reactivity then technetium, while the technetium is more reactive than silver. The silver is less reactive as compared to both given elements.
Destornilladores, alicates de corte diagonal, alicates de punta fina, alicates de bomba ajustable y cinta métrica con punta magnética
Answer : The mass of liquid sodium needed are, 
Explanation :
First we have to calculate the number of moles of liquid sodium.
where,
q = heat absorb = 1.20 MJ = 1.20 × 10⁶ J
n = number of moles of liquid sodium = ?
c = specific heat capacity = 
= change in temperature = 
Now put all the given values in the above formula, we get:
Now we have to calculate the mass of liquid sodium.
Molar mass of Na = 23 g/mol
Therefore, the mass of liquid sodium needed are,
This is a chemical reaction because a precipitate (solid) was formed from 2 liquids, and there was a color change as well
