Answer:
boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), polonium (Po) and astatine (At)
Explanation:
metalloids are elements that are in between the metals and nonmetals. they are in between because they have properties of both metals and nonmetals.
you can search "metalloids on the periodic table" and go to images to see what i mean :)
Answer:
Isotopes of an element are atoms of the same element that have different number of neutrons.
Answer:
2.79 °C/m
Explanation:
When a nonvolatile solute is dissolved in a pure solvent, the boiling point of the solvent increases. This property is called ebullioscopy. The temperature change (ΔT) can be calculated by:
ΔT = Kb*W*i
Where Kb is the ebullioscopy constant for the solvent, W is the molality and i is the van't Hoff factor.
W = m1/(M1*m2)
Where m1 is the mass of the solute (in g), M1 is the molar mass of the solute, and m2 is the mass of the solvent (in kg).
The van't Hoff factor represents the dissociation of the elements. For an organic molecule, we can approximate i = 1. Thus:
m1 = 2.00 g
M1 = 147 g/mol
m2 = 0.0225 kg
W = 2/(147*0.0225)
W = 0.6047 mol/kg
(82.39 - 80.70) = Kb*0.6047*1
0.6047Kb = 1.69
Kb = 2.79 °C/m
When given percents for an empirical formula problem, first consider all the percents as grams.
58.82% carbon —> 58.82 g carbon
27.45% nitrogen —> 27.45 g nitrogen
13.73% hydrogen —> 13.73 g hydrogen
Then convert the grams of all the elements to moles, based on their molar masses.
Carbon - 58.82 g / 12.01 g/mol = 4.898 mol carbon
Nitrogen - 27.45 g / 14.01 g/mol = 1.959 mol nitrogen
Hydrogen - 13.73 g / 1.008 g/mol = 13.62 mol hydrogen
Then divide all of the mole numbers by the smallest number of moles, which is in this case, the 1.959 mol of nitrogen.
Carbon - 4.898 / 1.959 = 2.5
Nitrogen - 1.959 / 1.959 = 1
Hydrogen - 13.62 / 1.959 = 7
You want whole numbers for all of your mole numbers, so multiply all of them by 2, since 2.5 isn’t a whole number.
Final answer: C5N2H14
