Answer:
an atom is the smallest particle of matter
a compound is a substance that has two or more atoms and element is the opposite of compound.
molecule is........,...............hope this helps
A). 4
.........................
Firstly, the chemical equation between the calcium metal and water will be:
Ca(s) + 2 H₂O(l) → Ca(OH)₂(aq) + H₂(g)
We can see from the equation the bubbles of hydrogen gas which are formed during the reaction stick to the surface of the metal and hence calcium floats on water.
The other metal that will float on the water during the reaction is magnesium which have the same chemical behavior like calcium, we can illustrate that by the chemical equation:
Mg(s) + 2 H₂O(l) → Mg(OH)₂(aq) + H₂(g)
A pure substance<span> has a definite and constant composition. A pure substance can be either an element or a compound, but the composition of a pure substance doesn’t vary.</span> Ex: salt or sugar<span>
</span>Mixtures are physical combinations of pure substances that have no definite or constant composition — the composition of a mixture varies according to who prepares the mixture. Ex: sand mixed with salt
Answer:
10/3 m/s. v=d/t. so 100/30 = 10/3
