how many atoms are in 0.5 mole of aluminum

Answer:

The most reactive compound is: Phenol  because the electron donating character of the alcohol group increases the rate of the reaction.

The least reactive compound is nitrobenzene

because the electron withdrawing character of the nitro group decreases the rate of the reaction.

Explanation:

Answer:

According to the law of conservation of energy, energy cannot be created or destroyed, although it can be changed from one form to another. KE + PE = constant. ... As the car coasts down the hill, it moves faster and so it's kinetic energy increases and it's potential energy decreases. hope this helps

Explanation:

Answer:

They cannot be destroyed or created however,

Explanation:

it can only be transformed or transferred from one form to another.

Answer:  

A i took the quiz

Explanation:

Answer:

C）52g KCl in 100g water at 80°C

Explanation:

A saturated solution is one that contains as much solute as it can dissolve in the presence of excess solute at that particular temperature.

A solutibility curve is a graph that shows the variability with temperature of the solubility of a solute in a given solvent. A solutibility curve can provide information of whether a solution formed frommthe solute and solvent are saturated or not at a given temperature.

From the solubility curve in the attachment below:

A) A saturated solution of NH₄Cl will contain about 52 g solute per 100 g sat 50 °C. Thus, a solution of 40 g NH₄Cl in 100 g water at 50 °C is an unsaturated solution.

B) A saturated solution of SO₂ at 10°C will contain about 70 g of solute in 100 g of water. Thus a solution of 2g SO₂ in 100g water at 10°C is an unsaturated solution.

C) A saturated solution of KCl at 80 °C will contain about 52 g of solute in 100 g of water. Thus, a solution of 52g KCl in 100g water at 80°C is a saturated solution.

D) A saturated solution of Kl at 20 °C will contain about 145 g of solute in 100 g of water. Thus, a solution of 120g KI in 100g water at 20°C is an unsaturated solution.

Answer:

4.80×10³ years

Explanation:

Let the original amount (N₀) of ²²⁶Rn = 1 g

Therefore,

12.5% of the original amount = 12.5% × 1 = 12.5/100 × 1 = 0.125 g

Next, we shall determine the number of half-lives that has elapse. This can be obtained as follow:

Original amount (N₀) = 1

Amount remaining (N) = 0.125 g

Number of half-lives (n) =?

N = 1/2ⁿ × N₀

0.125 = 1/2ⁿ × 1

0.125 = 1/2ⁿ

Cross multiply

0.125 × 2ⁿ = 1

Divide both side by 0.125

2ⁿ = 1/0.125

2ⁿ = 8

Express 8 in index form with 2 as the base

2ⁿ = 2³

n = 3

Thus, 3 half-lives has elapsed.

Finally, we shall determine the time taken for only 12.5% of the original sample of ²²⁶Rn to remain.

This can be obtained as follow:

Half-life (t½) = 1.60×10³ years

Number of half-lives (n) = 3

Time (t) =?

t = n × t½

t = 3 × 1.60×10³

t = 4.80×10³ years.

Thus, it will take 4.80×10³ years for 12.5% of the original sample of ²²⁶Rn to remain.

Answer:

Explanation:

[tex]\text{From the list of the options given; we are to identify the suitable techniques} \\ \\ \text{for the characterization of benzoic acid.}[/tex]

[tex]\text{The analytical method used to confirm the structure and functional groups}\\ \\ \text{present in the product is} \ \ \mathbf{IR \ spectroscopy.}[/tex]

[tex]\text{The technique used to separate pure products from any excess reagents,} \\ \\ \text{impurities, and byproducts is}\ \ \mathbf{Recrystallization.}[/tex]

[tex]\text{The quick, numeric analysis done to characterize the product and assess the purity is}[/tex][tex]\mathbf{melting \ point.}[/tex]

Answer:

CaO < BaO < KCl <KI

Explanation:

Let us remember that the solubility of an ionic substance in water depends on the magnitude of the lattice energy and the hydration energy.  If the hydration energy is equal to or is greater than the lattice energy, the substance dissolves in water.

However, the lattice energy depends on the size of the ions. The smaller the ions in the ionic compound, the higher the lattice energy and the lesser the solubility of the ionic compound.

KI has the least lattice energy and the highest solubility in water while CaO has the highest lattice energy and the least solubility in water.

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Answer: h3po4 + ca(oh)2 = h2o + ca3(po4)2

Explanation:

I hope this helped!

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- Zack Slocum

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Answer:

Neil Bohr

Explanation:

Thank me latur✊

Sodium chloride is the chemical name for salt and is composed of sodium and chlorine, so it is a compound.