Answer:
1.12 moles
Explanation:
To find the amount of moles, you need to use the Ideal Gas Law:
PV = nRT
In this equation,
-----> P = pressure (atm)
-----> V = volume (L)
-----> n = moles
-----> R = Ideal Gas constant (0.08206 atm*L/mol*K)
-----> T = temperature (K)
After converting the temperature from Celsius to Kelvin, you can plug the given values into the equation and solve for "n".
P = 1.00 atm R = 0.08206 atm*L/mol*K
V = 25.0 L T = 0. °C + 273 = 273 K
n = ? moles
PV = nRT
(1.00 atm)(25.0 L) = n(0.08206 atm*L/mol*K)(273 K)
25.0 = n(22.4)
1.12 = n
Answer:
i. Atomic radius of an atom is defined as the total distance from the nucleus to the outermost shell of the atom.
On moving from left to right ( Mg, K) in a period, more and more electrons get added up in the same shell and the attraction between the last electron and nucleus increases, which results in the shrinkage of size of an atom. Thus, decreasing the atomic radii of the atom on moving towards right of the periodic table.
As moving from top to bottom, there is an addition of shell around the nucleus and the outermost shell gets far away from the nucleus and hence, the distance between the nucleus and outermost shell increases.
Thus the order of atomic radii is : Ca > Mg > K
ii. The energy required to remove the last valence electron from isolated gaseous atom (first ionization energy) increases as we move from left to right in a period. It decreases on moving from top to bottom.
Thus the order of first ionization energy is : K > Mg > Ca
iii. The chemical properties depend on the valence elctrons and as the elements Mg and Ca both have two valence electrons , they have same chemical properties.
Write the equation for the reaction and balance it. In this case the equation is: 2NaOH + H2SO4 → Na2SO4 + 2H2O
Convert the given amount to moles. Molarity, “M” is moles per liter. The given amount is 25 ml of 1.2 M H2SO4. Since Molarity uses Liters, the volume must be converted from ml to L.
Use the mole ratio in this case 2 moles of NaOH to ! mole of H2SO4
Convert the moles to the required units. In this case the required units are grams. The formula weight in grams er mole.
25 ml H2SO4 * 1L/1000 ml * 1.2 Moles/L * 2 moles NaOH/1 mole H2SO4 * 40 g NaOH/ 1 Mole NaOH
Perform these calculations and you have the answer! Timothy, When doing homework, the answer is NOT the important thing, the METHOD is! These 4 steps, combined with required changes in units will sove ANY stoichiometric problem easily.
Answer;
They indicate the acidity level. That is, the less pH, the more acidic
Hope it helps :)
Answer:
C
Explanation:
C) an atom with an atomic number of 18
