Answer:
The correct answer is:
A solution feels warm after a cool solid is added to it (C)
Explanation:
Chemical changes among other results in a change of the temperature of the reactants, producing a product of higher temperature (exothermic reaction) or a product of lower temperature (endothermic reaction). In this case, the temperature of the product was higher than the reactants suggesting an exothermic reaction.
The other options however, suggests physical changes rather than a chemical changes;
A. the change of color of the water suggest mixing or water and color molecules.
B. solid changing into liquid is change of state, which is more of a physical change than chemical
D. Filtration is a physical process, hence the change is a physical change.
Answer:
Box is made up of <em>copper</em>, because density is <em>8.96 g/cm³.</em>
Explanation:
Given data:
Volume of box = 17.63 cm³
Mass of box = 158 g
Which metal box is this = ?
Solution:
First we will calculate the density of box then we will compare it with the density value of given metals.
d = m/v
d = 158 g/ 17.63 cm³
d = 8.96 g/cm³
The calculated density is similar to the given density value of copper thus box is made up of copper.
D. For plato users
(I've had the exact same one)
The theory of infinite universe and the theory of vacuum as a substance. First was disproved by the discovery of the big bang and the later by some experiments with light which have shown that vacuum is not a substance but empty space.
Answer:
This is like having enough energy to supply the world for centuries with just 1% of the sea's force? The amount of energy in it can supply energy therefore the one drop of tea is able to run her air conditioning for the rest of her life.
Explanation:
