The third one down: "When barium hydroxide is mixed with ammonium chloride, ice crystals form on the outside of the container."
This is because an endothermic reaction [process] takes in more energy than it releases. Therefore because a decrease in energy leads to a decrease in temperature, the ice crystals forming show that it must be a endothermic reaction [process].
Hope this helps! :)
AJ
valence electrons are the number of electrons in the outer shell. there can only be 8 electrons in the outer shell. The number of valence electrons can be used to determine how many bonds are needed.
For example: H2O
O (oxygen) has 6 valence electrons
H (hydrogen) has 1 valence electron
O needs 2 more electrons to be stable
H needs 1 more electron to be stable
O forms one bond with two H atoms to form H2O.
228 grams
start with mass of Cr multiply by molar mass of Cr mole to mole ratio between Cr and Cr2O3 times molar mass of Cr2O3
Answer:
seven electrons
Explanation:
Chlorine is present in group seventeen of periodic table. It is halogen element. All halogens have seven electrons in outer most valance shell.
The require only one electron to gain the stable electronic configuration or to complete the octet.
Electronic configuration of chlorine:
Cl₁₇ = 1s² 2s² 2p⁶ 3s² 3p⁵
Abbreviated electronic configuration:
Cl₁₇ = [Ne] 3s² 3p⁵
Properties of chlorine:
1. it is greenish-yellow irritating gas.
2. its melting point is 172.2 K
3. its boiling point is 238.6 K
4. it is disinfectant and can kill the bacteria.
5. it is also used in manufacturing of paper, paints and textile industries.
<span>A piece of lithium is placed on the surface of some water in a beaker. Hydrogen is given off and Lithium hydroxide is formed. The word equation would be as follows:
</span>
lithium<span> + </span>water<span>→ </span>lithium hydroxide<span> + </span>hydrogen
Hope this answers the question. Have a nice day.
