Answer:
When solutions of sodium carbonate and hydrochloric acid are mixed, the equation for the hypothetical double displacement reaction is: Na2CO3 + 2 HCl → 2 NaCl + H2CO3 Bubbles of a colorless gas are evolved when these solutions are mixed.
Answer:
The u (amu is the old unit name) is 1/12 of the weight of an 12C atom. The way the u is chosen ensures that all core and atom masses are multiples of 1(±0.1) u.
Explanation:
Further explanation if needed...
Carbon 12 was chosen because the chemical atomic weights based on C12 are almost identical to the chemical atomic weights based on the natural mix of oxygen. Simply because the atomic mass is defined as 1/12 of the mass of 12C. Others isotopes of carbon (13C mostly, with an abundance of 1.1% approximately) account for an average atomic mass slightly above 12.
<span> Substance 1 was activated by the heat and inactivated by ice, Substance 2 was activated by the change in concentration, and Substance 3 increased the surface area.</span>
If the element is oxidized, then it's oxidation number would increase.
Let's say we have the following reaction.
2H2O --> O2 + 2H2
To the left, the oxidation number of O is -2, as it is bonded to two H, which is always H+. To the right, we have O2, and all gases have a oxidation number of 0 (zero). We say that O has been oxidized.
