Answer:
Here's what I find.
Explanation:
Many scientists contributed to our model of the atom.
Among those who received the Nobel Prize for their work are:
1906 — J.J. Thomson — discovery of the electron
1908 — Ernest Rutherford — nuclear model of the atom
1922 — Niels Bohr — planetary model of the atom
1922 — Albert Einstein — quantum mechanical model of the atom
1935 — James Chadwick — discovery of the neutron
Answer:
-1071 Joules
Explanation:
The Joule was introduced as the SI unit for energy in 1925. One calorie is equal to approximately 4.184 joules(J). This is a conversion factor that we can write two ways:
(1cal/4.184J) or (4.184J/1cal)
(265 cal)*(4.184J/1cal) = 1071 J
Since the energy is leaving the system, it should be written with a minus sign: -1071J
To solve this questions you first need to find the number of moles of barium phosphate you have. The molar mass of barium phosphate is 601.93g/mol.
24.4/601.83 = 0.0402 moles barium phosphate
Then you need to use avagadro’s number, 6.022 x 10^23, which is the number of molecules or formula units in a mole.
6.022 x 10^23 * 0.0402 = 2.42 x 10^22 formula units