All categories

4 years ago

AH means that energy is from a reaction.

Chemistry

1 answer:

ExtremeBDS [4]4 years ago

4 0

<u>Answer:</u>

<em>A negative ∆H means that energy is given off from a reaction </em>

<u>Explanation:</u>

$2NO_2 (g)N_2 O_4 (g)\\\\\Delta H=-58 KJ per mol$

If the reaction has negative ∆H value then the reaction is exothermic

$N_2 O_4 (g)2NO_2 (g)\\\\\Delta H=+58 KJ per mol$

If the reaction has positive ∆H value then the reaction is endothermic

When Heat energy is given in the equation itself

If it is present on the left side it means that heat is absorbed and the reaction is Endothermic

If it is present on the right side it means heat is given off and the reaction is exothermic

You might be interested in

What is the name of chewed food formed in the mouth?

alisha [4.7K]

The answer is bolus.

7 0

2 years ago

A chemist examines an ionic compound that contains magnesium and one other element. She

Igoryamba

Group 7

Explanation:

The unknown element belongs to the seventh group on the periodic table of elements.

Ionic bonds are usually formed between metals and nonmetals. They formed by the transfer of electrons from the less electronegative specie to the more electronegative one.

The metals usually lose electron because they are highly electropositive species.

If we have a magnesium atom with two valence electrons.
To form ionic bonds, it must transfer the two electrons to another atom.
The other atom, a nonmetal must be ready to accommodate and receive the donated electrons.
This ensure that its own octet is complete.
Group 6 elements requires 2 electrons to have a complete octet.
They can receive the two electrons

But we were told that there are two atoms of that element for each of the magnesium atom;

the atom must have a capacity of collecting one electron each to be stable.

Such atoms are found in Group 7 on the periodic table.

learn more:

Ionic bond brainly.com/question/6071838

#learnwithBrainly

3 0

3 years ago

Which statement is not true of alkenes?

sladkih [1.3K]

Answer:

Explanation:

3 0

4 years ago

A helium filled weather balloon has a volume of 806 L at 20.9°C and 753 mmHg. it is released and rises to an altitude of 6.8 km,

OLEGan [10]

<h3>Answer:</h3>

1257.45 L

<h3>Explanation:</h3>

We are given;

Initial volume of Helium gas, V1 as 806 L
Initial temperature of Helium gas,T1 as 20.9°C
Initial pressure of Helium gas, P1 as 753 mmHg
Pressure of Helium at the altitude 6.8 km, P2 as 417 mmHg
Temperature of Helium gas at the altitude 6.8 Km, T2 as -19.1°C

But, K = °C + 273.15

Therefore, T1 = 294.05 K and T2 = 254.05 K

We are required to calculate the new volume of the balloon at 6.8 km.
To determine the new volume we are going to use the combined gas law.
According to the combined gas law, $\frac{P1V1}{T1}=\frac{P2V2}{T2}$

Thus, rearranging the formula;

$V2=\frac{P1V1T2}{P2T1}$

$V2=\frac{(753)(806L)(254.05K)}{(417)(294.05)}$

$V2=1257.45L$

Therefore, the volume of the balloon at an altitude of 6.8 km is 1257.45 L

7 0

3 years ago

How to reproduce with a dolphin?<br> and how long will it take for the dolphin baby to come out?

Sedaia [141]

Answer. Dolphin reproduction starts when a couple of dolphins mate. The copulation occurs belly to belly initiating the gestation period which varies according to the species but ranges from 11 to 17 months in the case of the killer whale, being 12 months for the common bottlenose dolphin.

6 0

3 years ago

A____H means that energy is ____ from a reaction.

AH means that energy is from a reaction.