B - Atomic number. Dmitri Mendeleev organised the table according to atomic weight, however this caused problems with elements such as iodine and tellurium, Iodine has a higher mass, but a lower atomic number. And to make iodine in the same group as similar elements (halogens), Mendeleev had to break his own rules and put it before tellurium in the table. Moseley fixed this problem by ordering the elements according to atomic (proton) number.
Answer:
In hyphen notation, the mass number is written after the name of the element. For example, in isotopic notation, the isotope of carbon that has a mass number of twelve would be represented as 12C . In hyphen notation, it would be written as carbon-12.
Explanation:
lol just took the question and looked it up online this was the first thing that i saw if its not correct im sorry
look good w small changes below:
Answer:
AB is an ionic compound. The electronegativity difference between A and B is greater.
AC is an ionic compound. The electronegativity difference between A and C is greater.
BC is a covalent compound because the electronegativity difference between C and B is small.
everything else look good!
Explanation:
32
2H
2
+O
2
→2H
2
O
Molecular mass of H
2
=2 g/mol
Molecular mass of O
2
=32 g/mol
From the balanced chemical equation,
2×2=4 g of hydrogen requires 32 g of Oxygen to react completely
The actual number of atoms of each element present in the molecule of the compound is represented by the formula known as molecular formula.
Molar mass of the unknown compound = 223.94 g/mol (given)
Mass of each element present in the unknown compound is determined as:
- Mass of carbon,
:

- Mass of hydrogen,
:

- Mass of chlorine,
:

Now, the number of each element in the unknown compound is determined by the formula:

- Number of moles of
:

- Number of moles of
:

- Number of moles of


Dividing each mole with the smallest number of mole, to determine the empirical formula:


Multiplying with 2 to convert the numbers in formula into a whole number:
So, the empirical formula is
.
Empirical mass = 
In order to determine the molecular formula:
n = 
n = 
So, the molecular formula is:
