A cook had a jar containing a sweet food and a jar containing a sour food. The image above shows the sweet and sour foods. At room temperature, both foods are liquids. The same amount of energy was transferred into both substances. Later, one of the foods had changed phase while the other had not. Which food changed phase, and how did it change?

a
The sweet food changed because the molecules were able to move fast enough to overcome the attraction between them. Its molecules now move away from each other.
b
The sweet food changed because the strong attraction between molecules made their movement slower. Its molecules now move around each other.
c
The sour food changed because the weak attraction between molecules let them move faster. Its molecules now move away from each other.
d
The sour food changed because the molecules were able to move fast enough to overcome the attraction between them. Its molecules now move in place.

a sequence is a function whose domain is the set of natural numbers.

natural numbers are all the negative and positive integers

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms

confused

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