An atom is the smallest unit of matter that has the properties of an element. It is composed of a dense core called the nucleus and a series of outer shells occupied by orbiting electrons. The nucleus, composed of protons and neutrons, is at the center of an atom.
Explanation:
Answer:
Graphics can sometimes convey more information in a brief amount of space than an author can explain in a paragraph.
The answer is D) a neutron.
When we say an atom's mass is, like 5 atomic mass units actually we are saying that the total number of the neutrons and protons in its nucleus is 5.
The mass of a neutron and a proton is each one atomic mass unit.
Mass of a neutron is approximately 1 atomic mass unit.
Answer: The amount of carbon-14 left after 10 years is 25 g
Explanation:
Formula used :

where,
a = amount of reactant left after n-half lives = ?
= Initial amount of the reactant = 100 g
n = number of half lives =
Putting values in above equation, we get:


Therefore, the amount of carbon-14 left after 10 years is 25 g
The balanced equation
for the reaction is
CO(g) + 2H₂(g) ⇄ CH₃OH(g)
The given
concentrations are at equilibrium state. Hence we can use them directly in
calculation with the expression for the equilibrium constant, k.
expression for k can be written as
k = [CH₃OH(g)] / [CO(g)] [H₂<span>(g) ]²
</span>[H₂<span>]=0.072 M
[CO]= 0.020M
[CH</span>₃OH]= 0.030 M
From substitution,
k = 0.030
M / 0.020 M x (0.072 M)²
k =
289.35 M⁻²
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Hence, equilibrium constant for the given reaction at 700 K is 289.35 M</span>⁻².
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