Answer:
c) There are sharp emission lines demonstrating discrete energy levels.
Explanation:
When an element emits energy in the form of radiation, it produces a spectrum of colors on a photographic plate. This spectrum can either be continuous or discrete. In continuous spectrum the spectrum continues without any discrimination between two regions. This represents the continuous emission of radiation, and thus the continuous emission of energy without any break.
On the other hand, the line spectrum consists of discrete and sharp lines, which shows the emission of radiation in a certain amount in a certain time, with a break between emission. Hence, the line spectra supports the quantization of energy.
The correct option is:
<u>c) There are sharp emission lines demonstrating discrete energy levels.</u>
Answer:
The answer to your question is molality = 0.61
Explanation:
Freezing point is the temperature at which a liquid turns into a solid if a solute is added to a solution, the freezing point changes.
Data
Kf = 1.86 °C/m
molality = ?
ΔTc = 1.13°C
Formula
ΔTc = kcm
Solve for m
m = ΔTc/kc
Substitution
m = 1.13 / 1.86
Simplification and result
m = 0.61
Answer:
<u>7.44 grams CaCl2 will produce 10.0 grams KCl.</u>
Explanation:
The equation is balanced:
I've repeated it here, with the elements corrected for their initial capital letter.
CaCl2( aq) K2CO3( aq) → 2KCl( aq) CaCO3( aq)
This equation tells us that 1 mole of CaCl2 will produce 2 moles of KCl.
If we want 10.0g of KCl, we need to convert that mass into moles KCl by dividing by the molar mass of KCl, which is 74.55 grams/mole.
(10.0 grams KCl)/(74.55 grams/mole) = 0.1341 moles of KCl.
We know that we'll need half that amount of moles CaCl2, since the balanced equation says we'll get twice the moles KCl for every one mole CaCl2.
So we'll need (0.1341 moles KCl)*(1 mole CaCl2/2moles KCl) = 0.0671 moles CaCl2.
The molar mass of CaCl2 is 110.98 grams/mole.
(0.0671 moles CaCl2)*(110.98 grams/mole) = 7.44 grams CaCl2
<u>7.44 grams CaCl2 will produce 10.0 grams KCl.</u>
The number of protons tells you which element the atom is. The number of protons is the element number (Hydrogen - 1, Helium - 2, etc.).
