Answer:
The correct answer is 0.36 mol
Explanation:
First we have to calculate the molecular weight (Mw) of H₃BO₃ from the molar masses of the elements:
Mw(H₃BO₃)= 3 x Molar mass H + Molar mass B + (3 x Molar mass O)
= 3 x 1 g/mol + 10.8 g/mol + (3 x 16 g/mol)
= 61.8 g/mol
The molecular weight indicates that there are 61.6 grams per mol of substance. The scientist has 22.5 g, thus we can calculate the number of moles of H₃BO₃ by dividing the mass into the molecular weight as follows:
Number of moles of H₃BO₃ = mass/Mw= (22.5 g)/(61.8 g/mol) = 0.36 mol
There are 0.36 mol of H₃BO₃ in 750.0 mL of solution.
> How many valence electrons does a helium atom have?
The electron configuration of Helium is simply 1s2. We see
that its outermost shell is the s shell and it contains 2 electrons, therefore
the number of valence electrons is also 2.
> What is the formula of the ion formed when potassium
achieves noble-gas electron configuration?
Potassium has a electron configuration of [Ar] 4s1. To
have an electron configuration of only [Ar] which is a noble gas, the one electron
from 4s1 should be removed, hence:
<span>K+</span>
Answer:
A. synthesis
Explanation:
The reaction given is a synthesis reaction in which two substances combines to give a product.
In this reaction:
4Fe + 3O₂ → 2Fe₂O₃
The reaction involves the formation of a single product from two or more reactants.
The formation of a compound from union of the constituent elements also falls into this category of reaction.
1.0566 gal.
H O W E V E R
the constant formula you can use for solving and simplifying equations such as these, you can simply look up the metric system online and figure one out. hoped this helped!
Answer:
Water
Explanation:
Sugar and salt would both be considered solutes, and out of vinegar and water, water is the most common solvent.
Have a nice day!
