Answer: 0.5 moles
Explanation:
Cr2(SO3)2 is the chemical formula for chromium sulphate.
Given that,
Amount of moles of Cr2(SO3)2 (n) = ?
Mass of Cr2(SO3)2 in grams = 128.9g
For molar mass of Cr2(SO3)2, use the atomic masses:
Chromium, Cr = 52g;
Sulphur, S = 32g;
Oxygen, O = 16g
Cr2(SO3)2 =
(52g x 2) + [(32g + 16g x 3) x 2]
= 104g + [(32g + 48g) x 2]
= 104g + [80g x 2]
= 104g + 160g
= 264g/mol
Since, n = mass in grams / molar mass
n = 128.9g / 264g/mol
n = 0.488 mole [Round the value of n to the nearest tenth which is 0.5
Thus, there are 0.5 moles in 128.9 grams of Cr2(SO3)2
Answer:
Explanation:
1)<u><em> Ionization equilibrium equation: given</em></u>
- H₂O(l) + H₂O(l) ⇌ H₃O⁺(aq) + OH⁻(aq)
2) <em><u>Ionization equilibrium constant, at 25°C, Kw: given</u></em>
<u>3) Stoichiometric mole ratio:</u>
As from the ionization equilibrium equation, as from the fact it is stated, the concentration of both ions, at 25°C, are equal:
- [H₃O⁺(aq)] = [OH⁻(aq)] = 1.0 × 10⁻⁷ M
- ⇒ Kw = [H3O⁺] [OH⁻] = 1.0 × 10⁻⁷ × 1.0 × 10⁻⁷ = 1.0 × 10⁻¹⁴ M
<u><em>4) A solution has a [OH⁻] = 3.4 × 10⁻⁵ M at 25 °C </em></u><em><u>and you need to calculate what the [H₃O⁺(aq)] is.</u></em>
Since the temperature is 25°, yet the value of Kw is the same, andy you can use these conditions:
Then you can substitute the known values and solve for the unknown:
- 1.0 × 10⁻¹⁴ M² = [H₃O⁺] × 3.4 × 10⁻⁵ M
- ⇒ [H₃O⁺] = 1.0 × 10⁻¹⁴ M² / ( 3.4 × 10⁻⁵ M ) = 2.9⁻¹⁰ M
As you see, the increase in the molar concentration of the ion [OH⁻] has caused the decrease in the molar concentration of the ion [H₃O⁺], to keep the equilibrium law valid.
Question:
a. Diffusion
b. Facilitated diffusion
c. Both
d. Neither
1. movement to area of lower concentration
2. movement across a membrane
3. steroid transport into cell
4. requires energy
5. movement assisted by proteins
6. glucose transport into cell
Answer:
The sorting is as follows
a. (1)
b. (5 and 6)
c. (1 and 2)
d. (4)
Explanation:
Diffusion is the movement of particles across a membrane from a high concentration region to one with a lower concentration of the diffusing substance
Here we have the correct sorting as follows
a. Diffusion
3. steroid transport into cell
b. Facilitated diffusion
5. movement assisted by proteins
6. glucose transport into cell
c. Both
1. movement to area of lower concentration
2. movement across a membrane
d. Neither
4. requires energy
Answer:
Heterogeneous mixture solution
Explanation:
The reason this is Heterogeneous is that you cant see each individual compound in the solution. If this was sand or any compund that is not desolvable or not fully desolved in water would be Homogenous since you can see the individual compounds (water and sand)
Ionic compounds are compounds that are formed together by a cation and an anion. A cation is an ion with a positive charge. For example, Na+ and Ca2+. An ion has a negative charge, like Cl- and OH-. There is a greater chance of forming an ionic compound when they have a great difference in electronegativity, the ability to attract electrons toward itself. In the periodic table, elements that are opposite to each other, more likely found in opposite sides, would be more apt to form an ionic compound. Example would be NaCl and CaCl2 or Ca(OH)2.