Answer:
The mass of copper = 208.26 grams.
Explanation:
Density = mass / volume
8.9 = mass / 23.4
mass = 8.9 * 23.4
= 208.26 grams.
The three broad classes of elements are:
Metals
Metalloids
Nonmetals
The answer will be
.
.
.
4.88 x 1023 molecules of O2
Explanation:
Speed and velocity are both used to describe the motion of a body. But there are differences between the two terms.
- Velocity is the rate of change of displacement with time. It is mathematically expressed below:
Velocity = 
The unit of velocity is m/s or km/hr.
Velocity is a vector quantity that shows magnitude and direction.
- Speed is the rate of change of distance with time. It is concerned with the total length of path a body moves.
Speed = 
It has the same unit as velocity
It is a scalar quantity that has only magnitude.
learn more:
Velocity brainly.com/question/10883914
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