Answer:
B. Convert mass percents to moles and then divide by the smallest mole value to get subscripts
Explanation:
The empirical formula is the smallest whole number ratio the elements in a compound can possess. According to this question, to derive the empirical formula of a compound from its percent composition of elements that make it up, the following steps are followed:
- First, since the elements are in percentage, one would assume the total mass of the compound is 100g and take each percentage as the mass of each element. For example, if a compound contains 16% oxygen, it means that 16g of oxygen is present.
- Next, we convert the mass of each element to moles by dividing the mass value by the molar mass of each element. For example, 16g of oxygen will be 16g/16g/mol = 1mol
- Next, we divide each mole value by the smallest mole value to get the subscript of each element that will be used in the empirical formula.
Answer:
1. trigonal-planar
Explanation:
NO3- (nitrate) has three domains around it and each oxygen pushes against each other creating a planar structure.
It is a good thing that you already have answered the first question. Now, moving on to the second question, there exist an equation for the neutralization of acid by a base that is shown below,
M₁V₁ = M₂V₂
Now, all the variables in the equation are given except for our unknown which is the V₂. Substituting the known values from the given above,
(0.1 M)(25 mL) = (0.05 M)(V₂)
The value of V₂ from the equation above is 50 mL. Therefore, 50 mL of 0.05 M NaOH solution will be needed to completely react with HNO3.
The correct answer is option 2. Chlorine gas molecules are held together by strong covalent bonds. This type of bond requires an ample amount of energy in order to break it and turn gas into liquid. That is why, high pressure and low temperature is needed.
