Calculate the number of kilojoules of energy required to convert 50.0 grams of solid DMSO initially at a temperature of 19.0°C t

Answer: The change in enthalpy for each mole of zinc involved in the reaction is 152.4 kJ/mol.

Explanation:

First, we need to determine the moles of Zn and HCl.

The molar mass of Zn is 65 g/mole

and,

Next, we must identify the limiting reagent and the excess reagent.

The chemical reaction given is:

According to the balanced reaction we find that

1 mole of reacts with 2 moles of

Thus, 0.0206 moles of react with moles of

This leads us to determine that is the excess reagent because the moles provided exceed the required moles, while is limiting and restricts product formation.

Now to find the enthalpy change for each mole of zinc reacting in this reaction.

From the reaction we gather that,[ [TAG_59]]

0.0206 moles of Zn yield heat = 3.14 kJ

This implies that 1 mole of Zn generates heat =

Hence, the enthalpy change per mole of zinc involved in this reaction amounts to 152.4 kJ/mol.

The answer is B. 45k. Human bodies contain approximately 60 to 70% water.

In a 100 g sample of the compound, there are 63.57 g of carbon, 6 g of hydrogen, 9.267 g of nitrogen, and 21.17 g of oxygen. First, convert these masses into moles (n) using the formula n = m/M, where M is the molar mass from the periodic table. For carbon: 63.57 g C -> 63.57 g C / 12.01 g/mol = 5.29 moles C. For hydrogen: 6 g H -> 6 g H / 1.008 g/mol = 5.95 moles H. For nitrogen: 9.267 g N -> 9.267 g N / 14.01 g/mol = 0.6615 moles N. For oxygen: 21.17 g O -> 21.17 g O / 16.00 g/mol = 1.32 moles O. Thus, the mole ratio looks like this: C 5.29 H 5.95 N 0.6615 O 1.32. Now, divide each value by the smallest number (1.32): C 4 H 4.5 N 0.5 O 1. To eliminate fractions, multiply all values by 2, yielding C8H9N1O2. Now, all numbers are integers! Hence, the empirical formula is C8H9NO2. Although the empirical formula isn't always the same as the molecular formula, in this instance, it corresponds to acetaminophen.

A secondary alkyl halide would be characterized by having a carbon atom connected to two other carbon atoms, with bromine attached to that carbon.

Therefore, bromo-hexane qualifies as a 2-degree or secondary alkyl halide

Answer:

C a B r 2 ( a q ) + N a 2 S O 4 ( a q ) ⟶ 2 N a B r ( a q ) + C a S O 4 ( s )

Explanation:

A precipitation reaction involves a displacement process where a solid precipitate forms. This precipitate, being solid, is distinct from the other products and can be separated.

C a 2 + ( a q ) + S O 4 2 − ( a q ) ⟶ C a S O 4 ( s )

This equation is incorrect as it results in only C a S O 4.

C a B r 2 ( a q ) + N a 2 S O 4 ( a q ) ⟶ 2 N a B r ( a q ) + C a S O 4 ( s )

This is the proper reaction where C a S O 4 precipitate is produced.

C a 2 + ( a q ) + 2 B r − ( a q ) + 2 N a + ( a q ) + S O 4 2 − ( a q ) ⟶ 2 N a + ( a q ) + 2 B r − ( a q ) + C a S O 4 ( s )

This equation illustrates the ionic details of the precipitation reaction.