It stays roughly the same size. Electrons have a barely imperceptible mass so the overall mass of the atom is changed very little.
Answer:
E²⁺
Explanation:
The group two contain alkaline earth metals.
There are six elements in group 2A.
Beryllium, Magnesium, calcium, strontium, barium and radium.
All members have two valance electrons.
They lose two valance electrons to complete the octet.
When they lose the two valance electrons they form cation X²⁺.
They react with halogens and form salt such as
MgCl₂, CaCl₂ etc.
Mg²⁺ Cl²⁻₂
The oxidation state of halogens are -1, while the elements of group two A shows +2 that's why two atoms of halogen are combine with one atom of alkaline earth metals and make the compound overall neutral.
All the alkaline earth metals have similar properties.
Please, observe that it is not right to say that a substance content heat.
Heat is not something that a body or substance content. Heat is the transmission of energy due to difference of temperatures.
An endothermic reactions is that where the reactants abosorb energy from the surroundings to occur. The products, then, will be higher in energy than the reactants while the surroundings get colder.
The statement of the combined gas law for a fixed amount of gas is,
PV/T = constant
Here, the units of pressure and volume must be consistent and the temperature must be the absolute temperature (Kelvin or Rankine).
0.65 atm is equivalent to 494 mmHg
Using the equation:
(755 x 500) / (27 + 273) = (494 x V) / (-33 + 273)
V = 3396 ml = 3.4 liters
Answer:
[NaOH} = 0.4 M
Explanation:
In a reaction of neutralization, we determine the equivalence point of the titration. In this case, we have a strong base and a strong acid.
(H₂SO₄, is considered strong, but the first deprotonation is weak)
2NaOH + H₂SO₄ → Na₂SO₄ + 2H₂O
As we have 2 protons in the acid, we need 2 OH⁻ from the base to form 2 molecules of water.
In the equivalence point we know mmoles of base = mmoles of acid
Let's finish the excersise with the formula
25 mL . M NaOH = 28.2 mL . 0.355M
M NaOH = (28.2 mL . 0.355M) / 25 mL → 0.400
