Answer:
a chemical change is when the substance turns into a new substance and can not be changed back into its original form
Explanation:
If the solute is properly distributed in the given volume, there are 2.642 g of (NH4)2SO4 per 10 mL. For the new solution, divide the 2.642 g by the molar mass of the compound. The answer is 0.02 moles. Then, divide this by the new volume, 50 mL or 0.05 L. The concentration of the new solution is 0.4 M.
Answer: Scientist shoot a whole bunch of neutrons at uranium-235 atoms. When one neutron hits the nucleus the uranium becomes U-236. When it becomes 236, the uranium atoms wants to spilt apart. After it splits it gives off three neutrons and a lot of energy.
Explanation:
Answer:
The correct answer is - 3.012×10^23 molecules
Explanation:
The number of molecules is present in any mole of an element or compound are the same. To find the molecules you need to multiply the number of the moles of the compound by Avogadro's number:
Moles are calculated from the molecular weight, for AlF3
= 26.98 + 3×19
= 26.98 + 57
= 83.98
Then moles in 42 grams:
= 42/83.98
= 0.5001190 moles
Now the number of molecules = moles*Avogadro's number
= 0.500110×6.022×10^23
= 3.011×10^23 molecules
