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ICE Princess25 [194]

2 years ago

15

a. Define Valency. b. Write the symbol and valency of the following : (i) Oxygen (ii) potassium 7. a. Magnesium burns in Oxygen

to form Magnesium Oxide. a) Name the reactants b) Name the Products c) Write the word equation for the above reaction.

2 answers:

sweet-ann [11.9K]2 years ago

6 0

Answer:

Oxygen-Symbol-O Potassium Symbol-K

34kurt2 years ago

6 0

<h3>⚘ <u>Your</u><u> </u><u>Answers</u><u>:</u></h3>

<u>A</u><u>)</u> Valency is the combining capacity of any element. Valence electrons refers to the electrons found in the outermost shell of the atom of the element.

<u>B</u><u>)</u> Symbol and valency:

Oxygen(O) = (At. no. 8) = -2(Valency)
Potassium(K) = (At. no. = 19) = +1(Valency)

<u>C</u><u>)</u> The reaction would be:

$\large{ \boxed{ \rm{2Mg + O_2 \longrightarrow \: 2MgO}}}$

<u>Reactants</u> = Magnesium and Oxygen
<u>Products</u> = Magnesium oxide
Word equation:

$\large{ \boxed{ \rm{Magnesium + Oxygen \longrightarrow Magnesium oxide.}}}$

<u>━━━━━━━━━━━━━━━━━━━━</u>

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