Answer:
0.5 × 10²³ atoms of iodine
Explanation:
Given data:
Mass of calcium iodide = 12.75 g
Number of atoms of iodine = ?
Solution:
First of all we will calculate the number of moles of calcium iodide.
Number of moles = mass/ molar mass
Number of moles = 12.75 g/ 293.9 g/mol
Number of moles = 0.04 mol
In one mole of calcium iodide there are two moles of iodine.
Thus in 0.04 moles:
0.04 mol × 2 = 0.08 moles of iodine
Now we will use the Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ atoms
0.08 moles of iodine × 6.022 × 10²³ atoms / 1 mol
0.5 × 10²³ atoms of iodine.
for liquid to gas, Evaporation or vaporization.
for gas to liquid, condensation occurs. The opposite of evaporation. Condensation is when the gas gives up it's latent heat and simply condenses.
Answer:
2.3 atm
Explanation:
-7.50°C = 265.5 K
38°C = 315 K
(2.72)(265.5)=(pressure)(315)
pressure = 2.3 atm
Answer:
These properties are basically the inverse of each other.
Explanation:
- Electronegativity is the tendency of an atom to attract an electron and make it a part of its orbital.
Ionization enthalpy, is the energy required to remove an electron from an atom.
- More electronegative atoms have high ionization enthalpies If the energy required to remove an electron is less, i.e. the atom has more tendency to give electron, it would thus have less tendency to take electron.
- Values and tendency of electronegativity in the periodic table: In general, the electronegativity of a non‐metal is larger than that of metal. For the elements of one period the electronegativities increase from left to right across the periodic table. For the elements of one main group the electronegativities decrease from top to bottom across the periodic table. To the subgroup elements, there’s no regular rule.
- Values and tendency of ionization potential in the periodic table: The first ionization energy is the energy which is required when a gaseous atom/ion loses an electron to form a gaseous +1 valence ion. The energy which is required for a gaseous +1 valence ion to loose an electron to form a gaseous +2 valence ion, is called the second ionization energy of an element. In general, the second ionization energy is higher than the first ionization energy of an element.
The first ionization energies of the elements of one period increase from the left to the right across the periodic table. According to the elements of main group, the first ionization energies generally decreases from top to bottom across the periodic table.
Answer: C) number of protons
