Rounded to 1 significant figure, 25 m would go to 30. This is because 0 isn't significant, so the 3 is the only significant figure.
Answer : The formula unit of Sr & Cl is
and the formula unit of Al & S is 
Explanation :
Formula unit : it is defined as the lowest number ratio of ions of an elements in an ionic compound or covalent compound.
For the formula unit of Sr & Cl, two chloride ions
are needed to neutralize the one strontium ion
.
For the formula unit of Al & S, three sulfide ions
are needed to neutralize the two aluminium ion
.
The formula unit of
and
are shown below.
Answer:
Ne 20: 10
and
Ne 22: 12
Explanation:
Ne-20:
N = A - Z = 20 - 10 = 10 neutrons
Ne-22:
N = A - Z = 22 - 10 = 12 neutrons
N: number of neutrons
A: mass number
Z: atomic number
The answer is:
:Avoid lying down after eating
That should help