<span>NaOH + HCl = NaCl + H2O</span>
(a) In this section, give your answers to three decimal places.
(i)
Calculate the mass of carbon present in 0.352 g of CO
2
.
Use this value to calculate the amount, in moles, of carbon atoms present in 0.240 g
of
A
.
(ii)
Calculate the mass of hydrogen present in 0.144 g of H
2
O.
Use this value to calculate the amount, in moles, of hydrogen atoms present in 0.240 g
of
A
.
(iii)
Use your answers to calculate the mass of oxygen present in 0.240 g of
A
Use this value to calculate the amount, in moles, of oxygen atoms present in 0.240 g
of
A
(b)
Use your answers to
(a)
to calculate the empirical formula of
A
thank you
hope it helpsss
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.
Answer : The true statements are:
(a) Emulsions are a type of colloid
(b) The particles of a colloid are larger than the particles of a solution
(d) Many colloids scatter light (tyndal effect)
Explanation :
Colloid : It is defined as the solution in which the one substance is insoluble in another solution that means the insoluble substance rotating in the solution.
The particles of a colloid are larger than the particles of a solution.
Colloid do not separate on standing.
Cannot be separated by filtration.
Scatter light (Tyndall effect).
For example :
Milk is considered as a colloid because various substances (fats, proteins etc..) are present in milk which are suspended in a solution.
Suspension : It is a heterogeneous mixture in which some of the particles are settle down in the mixture on standing or over time.
The particles in a suspension are far larger than those of a solution.
Emulsion : It is a mixture of two or more liquids that are normally immiscible.
Emulsions are a type of colloid.
Element Symbol Atomic Mass
Barium Ba 137.327
Hydrogen H 1.00794
Oxygen O 15.9994
Hope this helps, good luck
