Answer:
Explanation:
Given:
V1 = 200 ml
T1 = 20 °C
= 20 + 273
= 293 K
P1 = 3 atm
P2 = 2 atm
V2 = 400 ml
Using ideal gas equation,
P1 × V1/T1 = P2 × V2/T2
T2 = (2 × 400 × 293)/200 × 3
= 234400/600
= 390.67 K
= 390.67 - 273
= 117.67 °C
Answer:
2.30 × 10⁻⁶ M
Explanation:
Step 1: Given data
Concentration of Mg²⁺ ([Mg²⁺]): 0.039 M
Solubility product constant of Mg(OH)₂ (Ksp): 2.06 × 10⁻¹³
Step 2: Write the reaction for the solution of Mg(OH)₂
Mg(OH)₂(s) ⇄ Mg²⁺(aq) + 2 OH⁻(aq)
Step 3: Calculate the minimum [OH⁻] required to trigger the precipitation of Mg²⁺ as Mg(OH)₂
We will use the following expression.
Ksp = 2.06 × 10⁻¹³ = [Mg²⁺] × [OH⁻]²
[OH⁻] = 2.30 × 10⁻⁶ M
Answer:
decrease
Explanation:
Atomic radius
:
It is the distance from the center of nucleus to the outer most electronic shell.
Trend along period:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required
The values of x represents that number of moles of water molecules that is present per mole of the salt magnesium sulfate. To determine the value for this, we need to know how much is the water that is lost after heating the sample assuming that all of the water molecules are evaporated leaving only the unhydrated form of the salt. We calculate as follows:
Mass of hydrated salt = 3.484 g
Mass after heating = 1.701 g
Mass lost = 3.484 g - 1.701 g = 1.783 g
The mass lost is equal to the mass of water lost.
Moles water lost = 1.783 g ( 1 mol / 18.02 g ) = 0.0989 mol H2O
Moles of unhydrated salt = 1.701 g ( 1 mol / 120.37 g ) = 0.0141 mol MgSO4
moles water / moles MgSO4 = 0.0989 mol H2O / 0.0141 mol MgSO4 = 7
Therefore, the value of x is 7.
Answer:
The answer to your question is : letter B. 0.25 atm
Explanation:
To solve this problem we need to use the combined gas law:
<u>P₁V₁</u> = <u>P₂V₂</u>
T₁ T₂
Data
P1 = 0.99 atm V1 = 2 l T1 = 273K
P2 = ? V2 = 4 l T2 = 137K
Now, the clear P2 from the equation and we get
P2 = P1V1T2 / T1V2
Substitution P2 = (2 x 0.99 x 137)/(273 x 4)
P2 = 271.26 / 1092
Result P2 = 0.248 atm ≈ 0.25 atm
