Answer: See below
Explanation: a. The mass of an element is composed of:
protons: 1 amu each
neutrons: 1 amu each
electrons: 0 amu each
Only the protons and neutrons are counted in the atomic mass of an element
b. Electrons are assigned a mass of 0. They do have a mass, but it is exceedingly small compared to the protons and neutrons, so they are left out of the calculation of an element's mass.
c. An element becomes unstable if the neutrons exceed the protons by a certain ratio, dependent on the element.
Answer:
Four
Step-by-step explanation:
The <em>superscripts</em> in an electron configuration tell us how many electrons are in a subshell.
If the electron configuration is 1s¹ 2s¹2p², the total number of electrons is
1 + 1 + 2 = 4
The atom contains four electrons.
<em>Note</em>: this atom is in an <em>excited state</em>, because the 1s and 2s subshells can each hold one more electron.
The rate of a reaction rises as it progresses. The answer is false
<h3>What causes a reaction's rate to increase?</h3>
Generally speaking, raising the temperature of the reaction system, raising the concentration of a reactant in solution, and raising the surface area of a solid reactant will all raise the rate of a reaction. A catalyst can be added to the reaction mixture to speed up a process as well.
As reactants are used up, reactions often get slower with time. Catalysts are substances that, when added to a process, speed it up even if they are not themselves reactants.
learn more about reaction's rate refer
brainly.com/question/7578129
#SPJ4
Answer:
2016.417222 hours
Explanation: you def made your goal
28800 seconds
