Explanation:

Endothermic reactions are chemical reactions in which the reactants absorb heat energy from the surroundings to form products. These reactions lower the temperature of their surrounding area, thereby creating a cooling effect. Physical processes can be endothermic as well – Ice cubes absorb heat energy from their surroundings and melt to form liquid water (no chemical bonds are broken or formed).
When a chemical bond is broken, it is usually accompanied by a release of energy. Similarly, the formation of chemical bonds requires an input of energy. The energy supplied/released can be of various forms (such as heat, light, and electricity). Endothermic reactions generally involve the formation of chemical bonds through the absorption of heat from the surroundings. On the other hand, exothermic reactions involve the release of heat energy generated from bond-breakage.
Endothermic Reaction Examples
Ammonium nitrate (NH4NO3), an important component in instant cold packs, dissociates into the ammonium cation (NH4+) and the nitrate anion (NO3–) when dissolved in water
Answer:
carbon
Explanation:
cabonis not a conductor of heat
Chloride ions Cl –(aq) (from the dissolved sodium chloride) are discharged at the positive electrode as chlorine gas, Cl 2(g) sodium ions Na +(aq) (from the dissolved sodium chloride) and hydroxide ions OH –(aq) (from the water) stay behind - they form sodium hydroxide solution, NaOH(aq)
The two elements that have the same properties as sodium are potassium and rubidium .
<h3>What is periodic table?</h3>
The periodic table is an arrangement of the elements in order of increasing atomic number.
From the list, the two elements that have the same properties as sodium are potassium and rubidium .
Proton has an atomic number of 20 and a mass number of 40. The number of electrons is the same as the number of protons. Given that the atomic number is the number of protons present, we have 20 electrons and 20 protons.
Number of neutrons = Mass number - Number of protons
= 40 - 20 = 20 neutrons
Learn more about periodic table:brainly.com/question/11155928
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Answer:
hope this helps :)
Explanation:
for the first one, you can look at the periodic table and look at the atomic number and it will show you how many protons there are giving you the answer because protons and electrons are equal in a pure element
a- carbon
b- neon
c- boron
d- oxygen
e- helium
f- hydrogen
g- lithium
h- beryllium
i- nitrogen
1- sulfur
2- S
3- 16
4- 32.066
5- 16
6- 16
7- 16.066
8- draw circles and put 16 dots like on the other page and in the middle put 16 nuetrons and electrons
9- 6 i think