In general, a scientific law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. The explanation of a phenomenon is called a scientific theory.
so the third one should be correct.
Answer:
The correct options are: Z1) They tend to form cations, and Z4) They tend to form ionic compounds when they combine with the elements of Group VIIA.
Explanation:
The chemical elements that have a tendency of <u>losing their valence electrons</u> and are generally present on the <u>left-side of the periodic table</u> are known as metals.
The general characteristics of metals are malleability, ductility, lustre, high thermal and electrical conductivity.
The metals<u> readily lose their valence electrons</u> present in their valence electron shell to<u> form positively charged ions called </u><u>cation</u>s and thus have <u>low ionization energy</u>.
They also tend to form<u> </u><u>ionic compounds or salts</u><u> </u>with the <u>reactive non-metals belonging to the Group VIIA of the periodic table.</u>
<u>Therefore, </u><u>Z1 and Z4 </u><u>are the properties of most metals.</u>
If electrons are negative, losing an electron makes the ion positive.
Therefore Cu1+ contains 1 unpaired electron.
When carbon is burned in air carbon iv oxide gas is formed.
C (s) + O2 (g) = CO2(g) ΔH = - 393.5 kj/mol
The enthalpy change of the reaction is -393.5 j/mol which means that when one mole of carbon is completely burnt in air then 393.5 j of energy is evolved.
Thus, 1 mole = -393.5 j , then for 480 kj
= 480 × 1/393.5
= 1.2198 moles
1 mole of carbon iv oxide is equal to 44 g
thus, 1.2198 moles will be 1.2198 × 44 = 53.6712 g of CO2
The answer is D. The rules states that every orbital on every sub level must be occupied before any can be double occupied.
