Explanation:
1) from the periodic table for example if u looking for K it is from the group 1A so the valancey = +1 that is mean it loses one electron to reach a stable state. and this applied for the 1A , 2A, 3A groups.
if u looking for N it is from group 5A so its valency is -3
so it gain 3 electrons to reach a stable state to complete its orbital to 8 electrons. this applied to 5A, 6A,7A
for the transition metals and simimetals other rules.
2) neutral if the element does not hold any charge like
H2, O2, N2, Fe, Au, Cu ...
isotope : if the 2 elements have same symbol and atomic number but they differ in the mass number because the have different numbers of neutrons.
if the element is charged then it is considered as an ion ex: Fe2+ then it is iron cation ( +ion)
F- then it is fluoride anion (-ion)
if u have any doubt just writ a comment ( ;
We are given with
Cobalt phosphate - CoPO4
We are asked for the net ionic equation for the phosphate dissolving in H3O+
The net ionic equation is
CoPO4 (s) + H3O+ (aq) -----> HPO42- (aq) + Co3+ (aq) + H2O *(l)
Answer: The mass of the sample will be 1417.7 grams.
Explanation:
We are given:

This means that 1 mole of NaCl has an enthalpy of fusion of 30.2 kJ
1 mole of NaCl has a mass of 58.44 grams.
So, 30.2 kJ of heat is require for a mass 58.44 grams of NaCl
So, 732.6 kJ of heat will be required for =
= 1417.65 grams of NaCl.
Hence, the mass of NaCl sample will be 1417.7 grams.
Atoms like in chemistry class?
Answer:
When heat is added to a substance, the molecules and atoms vibrate faster. As atoms vibrate faster, the space between atoms increases. The motion and spacing of the particles determines the state of matter of the substance. The end result of increased molecular motion is that the object expands and takes up more space.
hope this helps!!!!!!