Answer:
The chemist would require to use 43.43 grams.
Explanation:
In order to solve this problem we need to know<u> how much do 0.550 moles of selenium weigh</u>. To do that we use selenium's<em> molar mass </em>and multiply it by the given number of moles:
- 0.550 mol * 78.96 g/mol = 43.43 g
The chemist would require to use 43.43 grams.
Answer:
X 154
Check solution in explanation
Explanation:
Average atomic mass = ( mass 1× abudance) + ( mass 2× abudance)+ ( mass 3× abudance) / 100
(149×13.8)+(152×44.9) +(154×41.3)/100
2056.2 + 6824.8 + 6360.2/100
=152.412
Answer:
Chemical energy found in the bonds between atoms
Nuclear energy found in nucleus of an atom
Electrical energy found in the flow of electrical charges
Thermal energy found when internal energy is transferred.
Answer: the percentage of acetic acid will be low.
Explanation: The major aim during titration of acids and bases is to determine the endpoint , that is exact point where the acid in the beaker changes colour, (in this case, pink )with an additional drop from the burette containing the base, since it is usually difficult to mark the equivalence point that tells us when all the substrate in the beaker has been neutralized completely with the buretted substance.
Overshooting the end point is an error which can occur when the person involved in the the titration accidently goes beyond this endpoint by adding too much of the substance(base) from the burette into the beaker missing the exact endpoint.
This implies that the person has added too much of the burreted liquid, ie the base than required , making the acid in the beaker to continue to react resulting to a lower concentration of the acid (acetic acid) with excess base.(NaOH)
<span>Molecular compounds, which are represented by molecules, are usually made of non-metals only (or of metalloids and non-metals). Ionic compounds, which are represented by formula units, are made of metals and non-metals.
More detail if you're interested: Molecules and formula units are the representative particles for molecular and ionic compounds, respectively. By that I mean, one unit of a molecular compound is a molecule...a bundle of atoms covalently bonded that exists separately from all the other molecules. One unit of an ionic compound is a formula unit. A formula unit is a representation of the compound's formula. For example, the formula unit of NaCl is one Na^+1 ion and one Cl^-1 ion. The formula unit of AlCl3 is one Al^+3 ion and three Cl^-1 ions. Ionic compounds don't have separate bundles of atoms like molecular compounds do, so the formula unit is just the smallest number of ions that it takes to represent the formula. </span>