When there are 14c-lable uracil that are added to the growth medium of cells, the macromolecules that will be labled are RNA. Uracil is a nucleobase that make up the DNA or the RNA. In RNA, uracil binds with other nucleobase (adenine) through hydrogen bonds.
Answer:
2.7 °C.kg/mol
Explanation:
Step 1: Calculate the freezing point depression (ΔT)
The normal freezing point of a certain liquid X is-7.30°C and the solution freezes at -9.9°C instead. The freezing point depression is:
ΔT = -7.30 °C - (-9.9 °C) = 2.6 °C
Step 2: Calculate the molality of the solution (b)
We will use the following expression.
b = mass of solute / molar mass of solute × kilograms of solvent
b = 102. g / (162.2 g/mol) × 0.650 kg = 0.967 mol/kg
Step 3: Calculate the molal freezing point depression constant Kf of X
Freezing point depression is a colligative property. It can be calculated using the following expression.
ΔT = Kf × b
Kf = ΔT / b
Kf = 2.6 °C / (0.967 mol/kg) = 2.7 °C.kg/mol
Answer:
The half-life of Material 1 and Material 2 are equal.
step by step explanation;
Material 1 disintegrates to half its mass three times in 21.6 s, to go from 100g
to 12.5g. That is,
100g - 50g - 25g - 12.5g
Material 2 disintegrates to half its mass three times in 21.6 s, to go from 200g to 25g. That is,
200g - 50g - 25g - 12.5g.
This means that regardless of their initial masses involved, material 1 and material 2 have equal half-life.
Their half-life is 21.6 ÷ 3 = 7.2 sec
Chromium is a chemical element with symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard and brittle metal which takes a high polish, resists tarnishing, and has a high melting point.
B. False. It is banned worldwide for agricultural uses. The <span>use of DDT is still authorized in small proportions in countries that need it, with support deployed for the alteration to safer and more effective alternatives.</span>
