The complete answer contains the answer choices.
This is the complete question:
Atoms of which element react spontaneously with Mg2+(aq)? (1)chromium
(2)barium
(3)iron
(4)zinc
Answer: option 2. barium.
Explanation.
1) Mg ²⁺ (aq) is the aquous cation of the metal Mg.
2) Only a metal more reactive than Mg will be able to exchange with it the oxidation states.
3) Mg is an earth alkalyne metal (group 2 of the periodic table). The metals from this group are more reactive than the metals in the groups to its right: 3, 4, 5, 6, 7, ... Only the alkalyne metals (those in group 1) are more reactive than the earth alkalyne metals.
4) Of the list, barium is the only alkalyne metal, so it is more reactive than Mg and will be able to deliver 2 electrons to transform the cations Mg²⁺ into Mg while the very Ba will become Ba²⁺.
5) Chromium, iron and zinc are transition metals, so less metallic (reactive) than Mg.
Answer:
The atomic number on the Periodic Table identifies the number of protons in any atom of that element. Copper, atomic number 29, has 29 protons. Finding the atomic number of an element reveals the number of protons.
To find the number of neutrons in the atom, subtract the atomic number from the atomic mass.
Answer:
Explanation:
<u>1) Data:</u>
a) V = 93.90 ml
b) T = 28°C
c) P₁ = 744 mmHg
d) P₂ = 28.25 mmHg
d) n = ?
<u>2) Conversion of units</u>
a) V = 93.90 ml × 1.000 liter / 1,000 ml = 0.09390 liter
b) T = 28°C = 28 + 273.15 K = 301.15 K
c) P₁ = 744 mmHg × 1 atm / 760 mmHg = 0.9789 atm
d) P₂ = 28.5 mmHg × 1 atm / 760 mmHg = 0.0375 atm
<u>3) Chemical principles and formulae</u>
a) The total pressure of a mixture of gases is equal to the sum of the partial pressures of each gas. Hence, the partical pressure of the hydrogen gas collected is equal to the total pressure less the vapor pressure of water.
b) Ideal gas equation: pV = nRT
<u>4) Solution:</u>
a) Partial pressure of hydrogen gas: 0.9789 atm - 0.0375 atm = 0.9414 atm
b) Moles of hygrogen gas:
pV = nRT ⇒ n = pV / (RT) =
n = (0.9414 atm × 0.09390 liter) / (0.0821 atm-liter /K-mol × 301.15K) =
n = 0.00358 mol (which is rounded to 3 significant figures) ← answer
The correct option is D. 0.2 M CaCl2 is has the lowest freezing point.
<h3>What is aqueous solution?</h3>
When one significance liquefies into another, a solution is formed. A solution is a homogenous mixture consisting of a solute dissolved into a solvent. The solute is the essence that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with multiple different classifications and forms of solutes and solvents. In this branch, we will focus on a resolution where the solvent is water.
- An aqueous solution is a moisture that contains one or more dissolved essence. The dissolved importance in an aqueous solution may be solids, gases, or different liquids.
- In directive to be a true solution, an assortment must be stable. When sugar is fully dissolved into moisture, it can stand for an undetermined amount of time, and the sugar will not recompense out of the solution. Further, if the sugar-water solution is passed through a filter, it will stay with the water.
- This is because the liquefied particles in a resolution are very small, usually less than 1nm in diameter. Solute particles can be atoms, ions, or molecules, counting on the type of essence that has been dissolved.
To learn more about aqueous solution, refer to:
brainly.com/question/14469428
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