Responder:
27
Explicación:
Dado que:
Número de protones en el átomo X = 29
Carga en el átomo X = +2
Si no hay cargo neto;
número de protones = número de electrones
Sin embargo, dado que el átomo X tiene una carga de +2 (dando 2 electrones).
Por lo tanto,
Número de electrones = número de protones - número de carga en el átomo)
Número de electrones = (29 - 2) = 27
The correct option is D. 0.2 M CaCl2 is has the lowest freezing point.
<h3>What is aqueous solution?</h3>
When one significance liquefies into another, a solution is formed. A solution is a homogenous mixture consisting of a solute dissolved into a solvent. The solute is the essence that is being dissolved, while the solvent is the dissolving medium. Solutions can be formed with multiple different classifications and forms of solutes and solvents. In this branch, we will focus on a resolution where the solvent is water.
- An aqueous solution is a moisture that contains one or more dissolved essence. The dissolved importance in an aqueous solution may be solids, gases, or different liquids.
- In directive to be a true solution, an assortment must be stable. When sugar is fully dissolved into moisture, it can stand for an undetermined amount of time, and the sugar will not recompense out of the solution. Further, if the sugar-water solution is passed through a filter, it will stay with the water.
- This is because the liquefied particles in a resolution are very small, usually less than 1nm in diameter. Solute particles can be atoms, ions, or molecules, counting on the type of essence that has been dissolved.
To learn more about aqueous solution, refer to:
brainly.com/question/14469428
#SPJ9
Answer:
2
Explanation:
In two reactions energy is released.
1) C₆H₁₂O₆ + 6O₂ → 6H₂O + 6CO₂ + heat
It is cellular respiration reaction.It involves the breakdown of glucose molecule in the presence of oxygen to yield large amount of energy. Water and carbon dioxide are also produced as a byproduct.
Glucose + oxygen → carbon dioxide + water + 38ATP
2) 2H₂ + O₂ → 2H₂O ΔH = -486 kj/mol
The given reaction is formation of water. In this reaction oxygen and hydrogen react to form water and 486 kj/mol is also released.
The reaction in which heat is released is called exothermic reaction.
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O → CO + H₂
ΔH = +131 kj/mol
it can be written as,
C + H₂O + 131 kj/mol → CO + H₂
F. <em>None of the above
</em>
<em>No O atoms are present</em> as reacting substances, only O_2 and H_2O molecules.
O_2 + 2H_2O + 2e^(-) → 4OH^(-)
We must use <em>oxidation numbers</em> to decide whether oxygen or water is the substance reduced.
The oxidation number of O changes from 0 in O_2 to -2 in OH^(-).
A decrease in oxidation number is <em>reduction</em>, so O_2 is the substance reduced.
The oxidation number of O is -2 in both H_2O and OH^(-), so water is <em>neither oxidized nor reduced</em>.
