Answer:
The atomic mass of the boron atom would be <em>10.135</em>
Explanation:
This is generally known as relative atomic mass.
Relative atomic mass or atomic weight is a physical quantity defined as the ratio of the average mass of atoms of a chemical element in a given sample to the atomic mass of 1/12 of the mass of a carbon-12 atom. Since both quantities in the ratio are masses, the resulting value is dimensionless; hence the value is said to be relative and does not have a unit.
<em>Note that the relative atomic mass of atoms is not always a whole number because of it being isotopic in nature.</em>
- <em>Divide each abundance by 100 then multiply by atomic mass</em>
- <em>Do that for each isotope, then add the two result. Thus</em>
Relative atomic mass of Boron = (18.5/100 x 11) + (81/100 x 10)
= 2.035 + 8.1
= 10.135
Answer:
4Al2O3 + 9Fe --> 3Fe3O4 + 8Al
Explanation:
Al:8 Al:8
O:12 O:12
Fe:9 Fe:9
just make sure that both sides have the same ammount. I started with Iron, balenced it to 3, then made sure i had 12 oxygen on both sides, being that i had 3 iron on the left and 9 on the right so i went back and fixed that. I then saw that i had 8 Al on the left and 1 on the right so i balenced that
The Alkali metals are Lithium, Sodium, Potassium, Rubidium, Caesium, and Francium. There may be Hydrogen as well, it really depends if the teacher considers it a metal. The Alkalis are the far left column on the periodic table. If you don't have a paper copy, www.ptable.com is a good resource.
Heat is transferred from air to the ice cubes, so that's why ice cube melt.