The third one down: "When barium hydroxide is mixed with ammonium chloride, ice crystals form on the outside of the container."
This is because an endothermic reaction [process] takes in more energy than it releases. Therefore because a decrease in energy leads to a decrease in temperature, the ice crystals forming show that it must be a endothermic reaction [process].
Hope this helps! :)
AJ
The relative formua for Potassium bromide is Kbr
Answer:The mole is important because it allows chemists to work with the subatomic world with macro world units and amounts. Atoms, molecules and formula units are very small and very difficult to work with usually. However, the mole allows a chemist to work with amounts large enough to use.
Explanation:
4. Molar mass of silver m Ms~=108 g/mol
Hence there are n=54*(1/108)=0.5 mols of Silver in 54 grams of Silver.
5. 6.3*(108/1)=680.4g
6. Avogadro's number : Na~=6.022×10^23<span>. </span>
6.0*(6.022*10^23/1)=36.132*10^23 atoms
7. Molar mass of Krypton : Mk=84 g/mol
112/84=1.33 moles of Kr
8. 1.93*10^24*(1/(6.022×10^23))=3.2 moles KF
9. Molar mass of Silicon : Ms=28 g/mol
86.2*(1/28)*(6.022×10^23/1)=18.5*10^23 atoms of silicon
10. Molar mass of Magnesium : M1=24 g/mol
4.8*10^24*(1/(6.022×10^23))*(24/1)=191 g Mg
