Answer:
This is not a chemical change
Explanation:
The dark green solution mixed with the water, but the water is still water. There were no bubbles, smell, temperature change, or any other signs of a chemical change
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Answer:
- <em>The vapor pressure of the solution at 25°C is </em><u><em>23.6 mmHg</em></u>
Explanation:
<u>1) Data:</u>
- Mass of solute, sucroese, m₁ = 40.0 g
- Mass of solvent, water, m₂ = 250. g
- Vapor pressure of solution, p = ?
- Vapor pressure of pure water, p⁰ = 23.76 mm Hg
<u>2) Principles and formulae:</u>
- Raoult's law states that the vapor pressure of a solution is equal to the mole fraction of the solvent times the vapor pressure of the pure liquid.
p = X p⁰
<u>3) Solution:</u>
a) <u>Mole fraction of the solvent (water)</u>
- X = number of moles of solvent / number of moles of solution
- number of moles of solvent, n₁ = mass in grams / molar mass
n₁ = 250. g / 18.015 g/mol = 13.88 moles
- number of moles of solute, n₂ = mass in grams / molar mass
n₂ = 40.0 g / 342,3 g/mol = 0.12 moles
- total number of moles, n₁ + n₂ = 13.88 moles + 0.12 moles = 14.0 moles
- moles fraction of water, X = 13.88 moles / 14.0 moles = 0.99
b) <u>Vapor pressure of the solution</u>:
- p = p⁰ X = 23.76 mmHg × 0.99 = 23.56 mm Hg
Rounding to three significant figures: 23.6 mm Hg.
Answer:
a. angiotensin II
Explanation:
Angiotensins are a set of peptide hormones that cause vasoconstriction and a subsequent increase in blood pressure, its main objective is to lower blood pressure.
Aldosterone is a hormone produced by the adrenal cortex that inhibits the level of sodium excreted in the urine, maintaining volume and blood pressure.
Nitric acid is a viscous and corrosive liquid that can cause severe burns in living things. It is used as a laboratory reagent and to make explosives such as nitroglycerin and trinitrotoluene, as well as fertilizers such as ammonium nitrate.
The atrial natriuretic peptide is a polypeptide and is related to the homeostatic control of body water, sodium, potassium and adipose tissue.
Answer:
b) beta decay
Explanation:
Beta radiations:
Beta radiations are result from the beta decay in which electron is ejected. The neutron inside of the nucleus converted into the proton an thus emit the electron which is called β particle.
The mass of beta particle is smaller than the alpha particles.
They can travel in air in few meter distance.
These radiations can penetrate into the human skin.
The sheet of aluminium is used to block the beta radiation
⁴₆C → ¹⁴₇N + ⁰₋₁e
The beta radiations are emitted in this reaction. The one electron is ejected and neutron is converted into proton.
Answer:
The equilibrium concentration of chlorine gas, Cl₂(g), is 0.0625 M
Explanation:
Chemical equilibrium is established when there are two opposite reactions that take place simultaneously at the same speed, so that no changes are observed as time passes, despite the fact that the substances present continue to react with each other.
The mathematical expression that represents Chemical Equilibrium is known as the Law of Mass Action and is stated as: The ratio of the product of high concentrations to the stoichiometric coefficients in the reaction of products and reactants remains constant at equilibrium. For any reaction:
aA + bB ⇄ cC + dD
the equilibrium constant Kc is calculated as:
In this case, you have:
2 ICl(g) → Cl₂(g) + I₂(g)
So, the equilibrium constant Kc is:
Being:
- Kc= 0.10
- [Cl₂]= ?
- [ICl]= 0.50 M
- [I₂]= 0.40 M
Replacing:
Solving:
0.1= 1.6 * [Cl₂]
[Cl₂]= 0.1 ÷ 1.6
[Cl₂]= 0.0625 M
<u><em>The equilibrium concentration of chlorine gas, Cl₂(g), is 0.0625 M</em></u>