A chemical equation does not give information about the following:
- It usually does not give the "state of the substances". There are three states: Solid(s), liquid(q) and gas(vap).
- The chemical equation does not show whether it is complete or incomplete.
- The "speed of the reaction" is not mentioned.
- The "concentration of the substance" whether it is diluted or concentrated is not mentioned.
- The "rate of the reaction", temperature, catalyst, pressure etc is not mentioned. These can be mentioned "above or below the arrow".
Answer:
1.The Aluminum block
2.its surroundings absorb energy from it.
Explanation:
In this question it is important to remember that density of an object is the mass of that object divided by its volume.
The expression applied here is density=mass/volume
Given that the mass is constant,lets say mass= m=1g
and density of aluminum=2.7g/cm³ and that of iron is 7.8 g/cm³ then volume=?
Volume=mass/density
Volume of aluminum= 1/2.7 =0.3704 cm³
Volume of iron = 1/7.8 =0.1282 cm³
Here we see volume of Aluminum block is the largest.
2.As water in an ice cube tray freezes, its surroundings absorb energy from it.When the water freezes, latent heat of freezing is given out to the surrounding.When water is freezing, it stays at a constant temperature of 0°C, the heat energy released ensures that there is no cooling past 0 °C.
Physical properties help identifying a substance and how it changes.
For example: if a substance crushes easily that means it has a low density, but if it’s hard and doesn’t crush easily, that means it has a strong high density.
And eventually the substance would not end up forming a new substance.
Look at the picture below to understand more about physical changes.