Answer:
Diamonds
Explanation:
The melting point of sugar is 186C
The melting point of oxygen is -218C
The melting point of diamonds are 4078C
Therefore diamonds have the highest melting point.
You can also think of their structures, as diamonds have a covalent network structure, meaning they are really strong and have a high melting point
Oxygen has a covalent molecular structure
Sugar has a much weaker covalent network structure
Common denominator - Find the Least Common Multiple of the denominators (which is called the Least Common Denominator).
Change each fraction (using equivalent fractions) to make their denominators the same as the least common denominator.
Then add (or subtract) the fractions, as we wish!
Least common denominator - You do the same thing for the common denominator
Answer:
Explanation:
wavelength λ = 12.4 x 10⁻² m .
energy of one photon = h c / λ
= 6.6 x 10⁻³⁴ x 3 x 10⁸ / 12.4 x 10⁻²
= 1.6 x 10⁻²⁴ J .
Let density of coffee be equal to density of water .
mass of coffee = 255 x 1 = 255 g
heat required to heat up coffee = mass x specific heat x rise in temp
= 255 x 4.18 x ( 62-25 )
= 39438.3 J .
No of photons required = heat energy required / energy of one photon
= 39438.3 / 1.6 x 10⁻²⁴
= 24649 x 10²⁴
= 24.65 x 10²⁷ .
<h3>
Answer:</h3>
0.255 moles
<h3>
Explanation:</h3>
- The relationship between moles, mass and the molar mass of a compound is given by;
- Molar mass of a compound is equivalent to the relative formula mass of a compound that is calculated by adding the atomic masses of atoms making the compound.
In our case.
We are given the compound PCl₃ whose;
Mass is 35 g
Molar mass is 137.33 g/mol
But;
Therefore;
= 0.255 moles
Therefore, 35 g of PCl₃ contains 0.255 moles
KMnO4 has the incorrect set of oxidation numbers. Whenever there is an alkali metal, it has an oxidation number of +1. As you can see, K is said to have an oxidation number of +2, so it is incorrect.
