A 150 g sample of water (initially at 45 C) is mixed with an unknown mass of water (initially at 84 C). the final temperature of the system is 67.3 C. Determine the mass of water

Answer : The unknown mass of water is, 200.3 grams.

Explanation :

In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.

As,

= specific heat water

So,

where,

= mass of water = 150 g

= mass of unknown water  = ?

= final temperature of mixture =

= initial temperature of water =

= initial temperature of unknown water =

Now put all the given values in the above formula, we get

Therefore, the unknown mass of water is, 200.3 grams.

asking the goog might u get an answer

- 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