The correct answer is B. Platinum is the transition element among the choices. The elements belonging to this group are those having a partially filled d or f subshell. It usually refers to the d-block transition elements of the periodic table.
Answer:
The reaction is endothermic.
Explanation:
Heat is absorbed in endothermic reactions. An endothermic process is any process which requires or absorbs energy from its surroundings, usually in the form of heat. It may be a chemical process, such as dissolving ammonium nitrate in water, or a physical process, such as the melting of ice cubes (wikipedia)
Standard Enthalpy of Reaction (ΔHrxn) is the amount of heat absorbed (+ΔH value) or released (-ΔH value) that results from a chemical reaction.
a. There are 1.85 moles in 2.00 × 10² g of silver (Ag).
b. There are 0.618 moles in 37.1 g of silicon dioxide (SiO₂)
<h3>What is the molar mass?</h3>
The molar mass is the mass in grams of 1 mole of particles, that is, the mass in grams of 6.02 × 10²³ particles. The units are g/mol.
We want to calculate the number of moles represented by different masses of different substances. In each case, the conversion factor between mass and moles is the molar mass.
- a. 2.00 × 10² g of silver (Ag)
The molar mass of silver is 107.87 g/mol.
2.00 × 10² g × (1 mol/107.87 g) = 1.85 mol
- b. 37.1 g of silicon dioxide (SiO₂)
The molar mass of silicon dioxide is 60.08 g/mol.
37.1 g × (1 mol/60.08 g) = 0.618 mol
a. There are 1.85 moles in 2.00 × 10² g of silver (Ag).
b. There are 0.618 moles in 37.1 g of silicon dioxide (SiO₂)
Learn more about molar mass here: brainly.com/question/21334167
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Ionic charge = +4
To answer this we look only at the protons and electrons. Because there are 4 more protons than electrons we know that this ion has 4 less electrons than it would need to have to have a neutral charge. Therefore, the ionic charge is +4
The little number at the top of the element