Which statement is generally true about cacl2?
it has only metallic bonds between the atoms.
it has only covalent bonds between the atoms.
its bonds are formed by large differences in electronegativity.
its bonds are formed by small differences in electronegativity.

Its bonds are formed by large differences in electronegativity.

Explanation:

The electronegativity of the elements present in the given compound are:

Calcium:1

chlorine: 3.16

thus the difference between calcium and chlorine is 2.16. which is considered a very large difference making the bond between calcium and chlorine purely ionic.

The other statements are false

1) It has only metallic bonds between the atoms.: there is no metallic bond. metallic bonds are present between metal atoms.

2) It has only covalent bonds between the atoms.: the covalent bond are formed between non metallic elements.

3) as calculated the difference is large thus this is also wrong Its bonds are formed by small differences in electronegativity.

the answer

explanation:

the capillary tube was too close to the bottom of the beaker.

the ruler may have moved.

water got into the capillary tube.

the temperature was not allowed to equilibrate in the 2-4 minutes.

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.