Answer:
Lead Pb
Explanation:
Firstly, we need to know what occurs when a radioisotope emits an alpha particle. An alpha particle is an helium atom. When an isotope emits an alpha particle, it loses an helium atom corresponding to subtracting 4 from its mass number and 2 from its atomic number. This of course coupled with the release of radiation.
Now, we polonium has a proton number of 84 and a mass number of 210. Subtracting 2 and 4 respectively from its proton and mass numbers will yield 82 and 206 proton and mass numbers respectively.
Hence, the decomposition of the Po-210 isotope will yield an element with 82 proton number and 206 mass number. This corresponds to the element Lead.
210Po ——> 206Pb + alpha particle + radiation
2NaN3 + H2O —> 2HN3 + Na2O
Answer:
→ 
Explanation:
Phosphoric acid is 
and barium hydroxide is 
. Since this is an acid-base reaction, our products should be water and a salt. Put these given compounds together as the reactants:
→ 
We need to balance this by making sure there are the same number of each atom on each side of the equation. Right now, on the left, we have:
- 5 H's
- 1 P
- 6 O's
- 1 Ba
On the right, we have:
- 2 H's
- 2 P's
- 5 O's
- 3 Ba's
To balance this, add a coefficient of 2 to the H3PO4, 3 to Ba(OH)2, and 6 to H2O:
→
Answer:
D-block
Explanation:
Transition metals are metals of the d-block elements located between group 2 and 3 in the periodic table. They are called d-block element because the filling of electrons in their electronic configuration ends in the d-orbital.
Now, they have variable oxidation state because of their partially filled 3d orbital i.e the 3d orbital is not completely filled.
