It's C, the amount of protons in the nucleus of each atom :)
Hi~~
H2O, commonly known as water, is definitely a compound.
David's conclusion is wrong because the hydrogen gas combined with oxygen from the air to form dihydrogen monoxide, also known as water.
Iron (III) chloride catalyzes the decomposition of hydrogen peroxide because the decomposition of hydrogen peroxide is usually inhibited by the presence of ions such as phosphate ions in solution. The iron ions that would result from the dissolution of iron (III) chloride have a charge of 3+ and would bond with the -3 charged phosphate ions, creating a non-charged FePO4 molecule and removing the decomposition inhibitor from the solution. Potassium iodide and potassium chloride both are more strongly bonded than a transition metal compound and would lack the necessary charged iron ion when added to hydrogen peroxide.
Answer:
Put their markers together, now they have each color
Explanation:
The position of hydrogen is controversial in periodic table because hydrogen is the only element with out neutron. it belongs to 1 st group but it is not placed there .