1 mole = 6.022×10^23 atoms. 1 water molecule = 2 Hydrogen atoms + 1 oxygen atom. So, 1 mole H2O = 1.2044×10^24 hydrogen atoms. Therefore 2 mole H2O will have 2.4088×10^24 hydrogen atoms.
Answer: The final temperature of nickel and water is
.
Explanation:
The given data is as follows.
Mass of water, m = 55.0 g,
Initial temp,
,
Final temp,
= ?,
Specific heat of water = 4.184
,
Now, we will calculate the heat energy as follows.
q = 
= 
Also,
mass of Ni, m = 15.0 g,
Initial temperature,
,
Final temperature,
= ?
Specific heat of nickel = 0.444 
Hence, we will calculate the heat energy as follows.
q = 
=
Therefore, heat energy lost by the alloy is equal to the heat energy gained by the water.

= -(
)
= 
Thus, we can conclude that the final temperature of nickel and water is
.
The thing that they have in common is that they are all non metals
Answer:

Explanation:
The unbalanced nuclear equation is

Let's write X as a nuclear symbol.

The main point to remember in balancing nuclear equations is that the sums of the superscripts and of the subscripts must be the same on each side of the reaction arrow.
Then
235 = 4 + A , so A = 235 - 4 = 231, and
92 = 2 + Z , so Z = 92 - 2 = 90
And your nuclear equation becomes

Element 90 is thorium, so
