Total mass of H2O2 in 20 grams of an aqueous H2O2 solution

What is the total number of hydrogen atoms in a molecule of heptyne?

Step2247 [10]

Answer:

12

Explanation:

alkyne formula is CnH2n-2

heptyne = 7

6 0

3 years ago

A hypothetical element has three main isotopes with mass numbers of 51, 53, and 54. If 15.00% of the isotopes have a mass number

Eva8 [605]

Answer: 53.25

Explanation: Please see attachment for explanation. Thanks.!

5 0

3 years ago

6. 100 ml of gaseous hydrocarbon consumes 300

mario62 [17]

Answer:

a. C₂H₄

Explanation:

At constant pressure and temperature, the mole ratio of the gases is equal to their volume ratio (a consequence of Avogadro's law).

Hence, the complete combustion reaction that has a ratio of 100 ml of gaseous hydrocarbon to 300 ml of oxygen, is that whose mole ratio is 1 mol hydrocarbon : 3 mol of oxygen.

Then, you must write the balanced chemical equations for the complete combustion of the four hydrocarbons in the list of choices, and conclude which has such mole ratio (1 mol hydrocarbon : 3 mol oxygen).

A complete combustion reaction of a hydrocarbon is the reaction with oxygen that produces CO₂ and H₂O, along with the release of heat and light.

a. C₂H₄:

C₂H₄ (g) + 3O₂ (g) → 2CO₂(g) + 2H₂O (g)

Precisely, for this reaction the mole ratio is 1 mol C₂H₄: 2 mol O₂, hence, this is the right choice.

The following analysis just shows that the other options are not right.

b. C₂H₂:

2C₂H₂ (g) + 5O₂ (g) → 4CO₂(g) + 2H₂O (g)

The mole ratio for this reaction is 2 mol C₂H₂ :5 mol O₂.

с. С₃Н₈

C₃H₈ (g) + 5O₂ (g) → 3CO₂(g) + 4H₂O (g)

The mole ratio is 1 mol C₃H₈ : 5 mol O₂

d. C₂H₆

2C₂H₆ (g) +7 O₂ (g) → 4CO₂(g) + 6H₂O (g)

The mole ratio is 2 mol C₂H₆ : 7 mol O₂

7 0

3 years ago

13. What is the symbol for Enthalpy change?

OverLord2011 [107]

Answer:

Explanation:

13 ) symbol of enthalpy change = Δ H .

14 ) enthalpy change is nothing but heat absorbed or evolved .

During fusion enthalpy change

Δ H .= m Lf , m is mass and Ls is latent heat of fusion

During evaporation, enthalpy change

Δ H .= m Lv , m is mass and Lv is latent heat of evaporation

during temperature rise , enthalpy change

Δ H = m c Δ T

In case of gas , enthalpy change can be calculated by the following relation

Δ H = Δ E + W , Δ E is change in internal energy , W is work done by gas.

15 ) When enthalpy change is negative , that means heat is released to the environment .So reaction is called exothermic .

when heat is absorbed enthalpy change is positive . Reaction is endothermic.

5 0

2 years ago

The expected o-c-h angle in this molecule is degrees. the expected hybridization at the central carbon is

WINSTONCH [101]

Each neutral carbon atom contains four valence electrons and may form up to four electron domains. Possible hybridizations include

$sp^{3}$ , four electron domains, as in ethane $\text{C}_2\text{H}_6$
$sp^{2}$ , three electron domains, as in ethene $\text{C}_2\text{H}_4$
$sp$ , two electron domains, as in ethyne $\text{C}_2\text{H}_2$

Molecules of each of the three hybridization demonstrate spatial configurations that would maximizes the separation between the electron domains.

Carbon atoms with a $sp^{3}$ hybridization would demonstrate a tetrahedral configuration with a bond angle of approximately $109.5\textdegree{}$
Carbon atoms with a $sp^{2}$ hybridization would demonstrate a triangular planar configuration with a bond angle of $120\textdegree{}$
Carbon atoms with a $sp$ hybridization would demonstrate a linear configuration with a bond angle of $180\textdegree{}$

Bond angles are characteristic of the spatial configuration of electron domains and identifies the hybridization of the central carbon atom.

Note that each hydrogen atom contains only one valence electron and would form only single bonds. It takes two valence electrons for oxygen atoms to achieve an octet such that each oxygen form only two bonds at a single time. Therefore given the fact that the carbon is bonded to both hydrogen and oxygen, only the following hybridizations are possible

$sp^{3}$ in which the oxygen atom forms a carbon-oxygen double bond with the central carbon atom;
$sp^{2}$ in which the oxygen atom forms a single bond with the central carbon atom and with a second atom.

3 0

3 years ago