Oxygen is a pure substance, as it is composed of only a single kind of atom. Which is the oxygen atom, it cannot be broken or degraded down any further into constituents that make up the element. In terms of both chemically and physically.
<h2>Hardness, lustre, and colour.</h2>
Explanation:
These Rocks shown in photographs are made of different types of minerals which have properties as follows:
●The color of the rock is grey, brown and yellow after it is ground into a powder its color is streak.
● The lustre of the rock tells how shiny the rocks are.
● Other properties include hardness, texture, shape, and size.
well you can't walk through the air but you can't walk through a concrete wall because all of the solid atoms holding it together
The constant used for the absorption of heat by the sample in melting is 
. Thus, option A is correct.
The chemical reaction has been defined as the energy in which the energy has been released or absorbed for the breaking of bonds in the reactants and the formation of product.
<h3>Constant for energy absorbed</h3>
The energy has been absorbed in the melting of the copper sample. Thus, the sample has been converted from the solid to the liquid state.
The change in energy with the conversion in solid and liquid state has been termed as heat of fusion.
The energy has been absorbed by the system, thus it has been marked with the positive sign.
Therefore, has been the constant used for the absorption of heat by the sample in melting. Thus, option A is correct.
Learn more about melting sample, here:
brainly.com/question/8828503
Answer:
I'm not sure
Explanation:
sorry wish that I did tho
