Dududuchcucu I h y y y y y red t e. Drrr. Erred tfyryt ty
When dT = Kf * molality * i
= Kf*m*i
and when molality = (no of moles of solute) / Kg of solvent
= 2.5g /250g x 1 mol /85 g x1000g/kg
=0.1176 molal
and Kf for water = - 1.86 and dT = -0.255
by substitution
0.255 = 1.86* 0.1176 * i
∴ i = 1.166
when the degree of dissociation formula is: when n=2 and i = 1.166
a= i-1/n-1 = (1.166-1)/(2-1) = 0.359 by substitution by a and c(molality) in K formula
∴K = Ca^2/(1-a)
= (0.1176 * 0.359)^2 / (1-0.359)
= 2.8x10^-3
<span>The volume of iron is obtained from the density formula (density= mass/ volume) given the density and mass. In this case, 4,540 grams of iron and a density of 7.86 g/ml are given. The volume obtained from formula is 493.64 ml or 5.78 dL. </span>
Its D. combustibillaty
A. density is how hard or densely the substances molecules are together
B.boiling point is the point at which bonds that hold molecules are broken and so the substances boils
C. malleability is how easily a substance can be stretched until it breaks
D. is a chemical property of how much chemical energy is stored in a substance for it to combust
hope that helps
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Answer:
The two statements are all True for group 7 and 8 elements.
Explanation:
The Group 7 elements are known as the halogens. They are reactive non-metals and are always found in compounds with other elements. Chlorine, bromine and iodine are all halogens.
Chlorine, bromine and iodine are the three common Group 7 elements. Group 7 elements form salts when they react with metals. The term ‘halogen’ means 'salt former'.
In addition to the discription given to norble gases in the question which is true, norble gases;
- are inert gases located on the right of the periodic table.
- have a full-set of valence electrons, so they're stable, unreactive
- are colorless, odorless and tasteless.
- have low melting and low boiling points.
- can be found in small amounts in the Earth's crust and the Earth's atmosphere.