Na has a +1 charge, and O has a -1 charge.
Explanation:
For the given reaction:
Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

![Rate=k[CO]^x[H_2]^y](https://tex.z-dn.net/?f=Rate%3Dk%5BCO%5D%5Ex%5BH_2%5D%5Ey)
where x and y are order wrt to
and 
According to collision theory , the molecules must collide for a reaction to take place. According to collision theory , the rate of a reaction is proportional to rate of collision of reactants.
Thus with an increase in concentration of reactants , the rate of reaction also increases. This is because if the concentration of reactants increases , the chances of collision between molecules also increases and thus more products wil be formed which in turn increases the rate of reaction.
Covalent since they are both non metals, a metal and a non metal make an ionic bond
Answer:
Er-144 -------> Dy-140 + He-4
Explanation:
Alpha decay is the release of a hydrogen nucleus. So the original atom will decrease the mass by 4 and the atomic number by 2.
Answer:
Wide melting point range - impure sample with multiple compounds
Experimental melting point is close to literature value - pure sample of a single compound
Experimental melting point is below literature value - impure sample with multiple compounds
Narrow melting point range - pure sample of a single compound
Explanation:
The melting point of substances are easily obtainable from literature such as the CRC Handbook of Physics and Chemistry.
A single pure substance is always observed to melt within a narrow temperature range. This melting temperature is always very close to the melting point recorded in literature for the pure compound.
However, an impure sample with multiple compounds will melt over a wide temperature range. We also have to recall that impurities lower the melting point of a pure substance. Hence, the experimental melting point of an impure sample with multiple compounds is always below the literature value.