Answer:
The cube A is magnesium, the cube B is aluminum and the cube C is silver.
Explanation:
Density is defined by the expression 
where m is the mass and V is the volume, therefore:
- Density of the cube A:
- Density of the cube B:
- Density of the cube C:
Solving for mass:
And all the three cubes have the same mass, so:
Therefore:
(Eq.1)
(Eq.2)
Solving for 
in Eq.1:
Replacing values for the volume:
As we know the density of the aluminum is 
, so replacing this value for 
:
that is the density of the magnesium.
Solving for 
in Eq.2:
That is the density of the silver.
Therefore the cube A is magnesium, the cube B is aluminum and the cube C is silver.
Answer:
covalent bond is the answer
Answer:
A neon lamp was switched on during the Great Depression and continued to burn until it was discovered some 77 years later. The electricity bill came up to a whopping $17 000!
Explanation:
Washing your hands before eating?
Explanation:
A change that does not cause any change in chemical composition of a substance is known as a physical change.
For example, mass, density, volume etc are all physical changes.
On the other hand, a change that brings change in chemical composition of a substance is known as chemical change.
For example, combustion, toxicity, reactivity etc are all chemical changes.
Hence, following statements are identified as chemical or physical changes as follows.
(a) Oxygen gas supports combustion : Chemical change
(b) Fertilizers help to increase agricultural production : Chemical change
(c) Water boils below 
on top of a mountain : Physical change
(d) Lead is denser than aluminum : Physical change
(e) Uranium is a radioactive element : Chemical change
