<u>Answer:</u>
Carbon and silicon both are tetravalent elements as compared to germanium, tin, and lead which are divalent.
That's because Ge, tin, and Pb show inert pair effect and has a greater nuclear effective charge on the 's' electrons due to poor shielding effect. .That's why these elements are not able to share their valence electrons while carbon and silicon does and show "catenation" which is the ability to form long chain molecules.
Answer:
B. Equal amounts of all gases have the same volume at the same
conditions
Explanation:
Amedo Avogadro found the relationship between volume of a gas and the number of molecules contained in the volume.
The law states that "equal volumes of all gases at the same temperature and pressure contains equal number of molecules or moles".
The law describes the behavior of gases when involve in chemical reactions. It enables one to change over at will in any statement about gases from volumes to molecules and vice versa.
So, the right option is B which implies that equal amounts of all gases have the same volume at the same conditions.
<span>
Correct Answer:
Option 3 i.e. 30 g of KI dissolved in 100 g of water.
Reason:
Depression in freezing point is a
colligative property and it is directly proportional to molality of solution.
Molality of solution is mathematically expressed as,
Molality = </span>

<span>
In case of
option 1 and 2, molality of solution is
0.602 m. For
option 3, molality of solution is
1.807 m, while in case of
option 4, molality of solution is
1.205 m.
<u><em>Thus, second solution (option 2) has highest concentration (in terms of molality). Hence, it will have lowest freezing point</em></u></span>