Answer:
Explanation:
First, we find in the tables the ΔH of formation of each compound. As you can see in the (image 1)
Then we solve the ecuation for ΔH°reaction
ΔH°reaction=∑ΔH°f(products)−∑ΔH°f(Reactants)
ΔH°reaction= (-2* 393.5 - 2*285.8) - (52.4 + 0) kJ/mol
ΔH°reaction = -1.41 *10^3 kJ/mol
Answer:
- <em>The net charge of the ionic compound calcium fluoride is </em><u><em>zero (0).</em></u>
<em>Explanation:</em>
<em>Ionic compounds,</em> such as covalent ones, have zero net charge; this is, they are neutral.
Substances with net positive charge are cations and substances with net negative charge are anions.
The charges in the <em>ionic compound calcium flouride</em> are distributed in this way:
- Calcium charge: Ca²⁺: this is, each calcium ion has a 2 positive charge
- Fluoride charge: F⁻: each fluoride ion has a 1 negative charge.
- Then, the <em>net charge</em> is: 1 × (2+) + 2 × (1-) = +2 - 2 = 0.
So, a two positve charge, from one calcium ion, is equal to two negative charges, from two fluoride tions, yielding a <u>zero net charge</u>.
Answer: Option (c) is the correct answer.
Explanation:
Activation energy or free energy of a transition state is defined as the minimum amount of energy required to by reactant molecules to undergo a chemical reaction.
So, when activation energy is decreased then molecules with lesser amount of energy can also participate in the reaction. This leads to an increase in rate of reaction.
Also, increase in temperature will help in increasing the rate of reaction.
Whereas at a given temperature, every molecule will have different energy because every molecule travels at different speed.
Hence, we can conclude that out of the given options false statement is that at a given temperature and time all molecules in a solution or a sample will have the same energy.
The reaction gives out a yellow showery sparks and produces a black solid. Iron reacts with dilute hydrocloric acid to give iron chloride and hydrogen gas.
2Fe+2Hcl3 = 2FeCl3+H2
Because the speed of light is determined by the medium that is it in. If light is in a vacuum it goes 300 million meters per second but it is slower in air, and even slower in water because water is more dense than the previous two.
