Answer:
10.60 grams of silane gas are formed.
Explanation:
From the reaction:
Mg₂Si(s) + 4H₂O(l) → 2Mg(OH)₂(aq) + SiH₄(g)
We know that the limiting reactant is Mg₂Si, so to find the mass of SiH₄ formed we need to calculate the number of moles of Mg₂Si:
Where:
m: is the mass of Mg₂Si = 25.0 g
M: is the molar mass of Mg₂Si = 76.69 g/mol
Now, the stoichiometric relation between Mg₂Si and SiH₄ is 1:1 so:
Finally, the mass of SiH₄ is:
Therefore, 10.60 grams of silane gas are formed.
I hope it helps you!
Answer:
22.7 g of CaCl₂ are produced in the reaction
Explanation:
This is the reaction:
CaCO₃ + 2HCl → CaCl₂ + CO₂ + H₂O
Now, let's determine the limiting reactant.
Let's divide the mass between the molar mass, to find out moles of each reactant.
29 g / 100.08 g/m = 0.289 of carbonate
15 g / 36.45 g/m = 0.411 of acid
1 mol of carbonate must react with 2 moles of acid
0.289 moles of carbonate will react with the double of moles (0.578)
I only have 0.411 of HCl, so the acid is the limiting reactant.
Ratio is 2:1, so I will produce the half of moles, of salt.
0.411 / 2 = 0.205 moles of CaCl₂
Mol . molar mass = mass → 0.205 m . 110.98 g/m = 22.7 g
Hi there! Air and sunlight can definitely be reused. Those are abundant and renewable resources. Therefore, A and D are eliminated. There is a limited amount of water, however, it's impossible to run out of it to the point that there's no more on Earth. C is out. The only answer choice that makes sense is coal, because it's a nonrenewable resource, and it takes millions of years to make more of. It's a fossil fuel, so once we use them up, we can't get anymore during our lives. The answer is B: coal.
Answer: option D. The attractive forces between the sodium and chloride ions are overcome by the attractive forces between the water and the sodium and chloride ions.
Explanation:
<em>Solid sodium chloride</em> (NaCl) is a ionic compound formed by ionic bonds between by the positive, metallic cations of sodium atom, Na⁺, and the negative, non-meatllic anions of chlorine atom, Cl⁻ (chloride).
Ionic bonds, then, are the electrostatic attracion between oppositely charged particles (cations and anions).
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<em>When solid sodium chloride dissolves in water</em>, the ions (cations and anions) are separated in the solvent (water) due to the superior attracitve forces between such ions and the polar water molecules.
<em>Water</em> (H₂O) is a molecule, formed by polar covalent bonds between two hydrogen atoms and one oxygen atom.
The polarity of water molecule is due to the fact that oxygen atoms are more electronegative than hydrogen atoms, which cause that the electron density is closer to oxygen nuclei than to hydrogen nuclei. This asymmetry in the electron density conferes a partial positive charge over each hydrogen atom and a partial negative charge over the oxygen atoms.
Thus, the positively charged hydrogen atoms attract and surround the negative chloride (Cl⁻) anions, while the negatively charged oxygen atoms attract and surround the positive sodium (Na⁺) cations. It is only because the attractive forces between the water and the sodium and chloride ions are stronger than the attractive forces between the sodiium and chloride ions that such ions may be kept separated in the solution. This process is called solvation and the ions are said to be solvated by the water molecules.
