The molar mass of sodium is 22.99 ㅤ ㅤ ㅤ 22.99 (28) = 643.72 mol now multiply by avogrados number to find the number of atoms. ㅤ ㅤ ㅤ 643.72 (6.022 x 10^23) = 3.88 x 10^26 number of atoms
Answer:
b. ΔE rxn is a measure of heat
Explanation:
a. ΔHrxn is the heat of reaction. <em>TRUE. </em>ΔHrxn or change in enthalpy of reaction is per definition the change in heat that is involved in a chemical reaction.
b. ΔErxn is a measure of heat. <em>FALSE. </em>Is the change in internal energy of a reaction
c. An exothermic reaction gives heat off heat to the surroundings. <em>TRUE</em>. An exothermic reaction is a chemical reaction that releases heat.
d. Endothermic has a positive ΔH. <em>TRUE. </em>When a process is exothermic ΔH<0 and when the process is endothermic ΔH>0
e. Enthalpy is the sum of a system's internal energy and the product of pressure and volume. <em>TRUE. </em>Under constant pressure and volume the formula is ΔH = ΔE + PV
I hope it helps!
Answer:
An atom is made of up subatomic particles called protons, neutrons and electrons. The center of an atom is called the nucleus and is where the protons and neutrons are held while electrons orbit the nucleus in orbital shells. A electron has a negative charge, a proton has a positive charge, and a neutron has no charge (neutral).
The atomic number of a atom is the total amount of the atom's protons. In a neutral atom (Not an ion), the amount of electrons is the same as the protons. Therefore, the atomic number also tells the amount of electrons in the atom.
A ion is a negatively or positively charged particle due to the giving or taking of electrons with one or more atoms (Called an ionic bond). An atom that gives away electrons becomes positively charge because that atom now has more protons than neutrons. An atom that takes an electron becomes negatively charge because that atom now has more electrons than protons.
Atomic Mass is the sum of an atom proton and neutrons. To determine how many neutron an atom has, subtract the atomic mass from the atomic number. Electrons do not play a part in atomic mass as their mass is 1/1,836 of a proton's mass.
A isotope is two or more forms of the same element that contain equal amounts of protons but different amount of neutrons.
An aqueous solution of hydrozen chloride: Strongly corrosive acids
A colouriess punpent liquid widely used in manufacturing plastic and pharmaceutical
