Answer: " <span>1.8 * 10²⁴ molecules of O₂ " .
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3.0 moles O₂ * (6.02 * 10²³ molecules O₂ / 1 mol O₂) =
[ (3.0) *(6.02 * 10²³) ] molecules O₂
= 1.806 * 10²⁴ ; round to 2 significant figures.
= 1.8 * 10²⁴ molecules of O₂ .
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<span>88 and 84 are mass numbers
the mass number of an element is the sum of the number of protons and the number of neutrons (in which they are each equal to 1 unit (amu))
the number of protons is always the same for a given element (e.g. any C atom has 6 protons), but the number of neutrons varies. Two atoms of the same element (number of protons) with a different number of neutrons are called "isotopes".
So the two strontium atoms differ by 4 neutrons. 84Sr has four neutrons less than 88Sr</span>
Answer:
T2 = 133.333°K
Explanation:
Using Combined Gas Laws:
(600 torr)(10L)/500°K = (200 torr)(8L)/x°K

Cross multiply:
x°K (600 torr)(10L) = 500°K(200 torr)(8L)
Divide:
x°K = (500°K(200 torr)(8L))/(600 torr)(10L)

x = 400/3°K or 133.333°K
Answer:
Actions that you have trained yourself to perform.
they are obtained by experience. they are not passed from generation. they can be learnt or abolished. Higher center's of brain is responsible for conditional reflexes
Explanation:
example riding a bike, swimming, typing
Answer:
Sr, Mg, P, F
Explanation:
The trend for decreasing radii size is up and to the right of the Periodic Table.