The empirical formula : CH₃
<h3>Further explanation</h3>
Given
2.5 g sample
2.002 g Carbon
Required
The empirical formula
Solution
Mass of Hydrogen :
= 2.5 - 2.002
= 0.498
Mol ratio C : H :
C : 2.002/12 = 0.167
H : 0.498/1 = 0.498
Divide by 0.167 :
C : H = 1 : 3
Answer:
Spindle fibers form.
DNA condenses into chromosomes.
Explanation:
Prophase is the first stage of mitosis. Mitosis produces 2 daughter cells from a parental cell.
Spindle fibers form - this is true. During prophase, the mitotic spindle forms. Later during mitosis the spindle attaches to the centromere of chromosomes and pulls them to opposite ends of the cell prior to division
DNA condenses into chromosomes. - this is true. In the nucleus during interphase, the DNA is relatively loosely compacted. However, prior to division, the DNA is condensed into structures called chromosomes which are then paired up and distributed to the daughter cell.
Chromosomes move to opposite ends of the cell. - this is false. This happens during anaphase
Nuclear membrane begins to re-form. - this is false. This happens during telophase.
Just add up the molar masses of each element.
Molar mass of C: 12.011 g/mol
The equation says C20, which means there are 20 carbon atoms in each molecule of Vitamin A. So, we multiply 12.011 by 20 to get 240.22 g/mol carbon.
Molar mass of H: 1.0079 g/mol
The equation says C30, which means there are 30 hydrogen atoms in each molecule of Vitamin A. So, we multiply 1.0079 by 30 to get 30.237 g/mol hydrogen.
Molar mass of O: 15.999 g/mol
The equation says O without a number, which means there is only one oxygen atom in each molecule of Vitamin A. So, we leave O at 15.999 g/mol.
Then, just add it up:
240.22 g/mol C + 30.237 g/mol H + 15.999 g/mol O = 286.456 g/mol C20H30O
So, the molar mass of Vitamin A, C20H30O, is approximately 286.5 g/mol.