Answer:
57
Explanation:
57 it's a good thing I didn't get a chance
Answer:
You just have to take the periodic table of the elements, take the element that interests you. Then, you look at the formula of the element, at the top left you find the number of neutrons and protons and at the bottom left you find the number of protons. Then you just have to make the number from the top left minus the number from the bottom left.
Explanation:
Answer:
Nucleus
Explanation:
The nucleus serves as the cells command center, sending direction to the cell to grow, mature, divide, or die
Answer:
- <em>Hydration number:</em> 4
Explanation:
<u>1) Mass of water in the hydrated compound</u>
Mass of water = Mass of the hydrated sample - mass of the dehydrated compound
Mass of water = 30.7 g - 22.9 g = 7.8 g
<u>2) Number of moles of water</u>
- Number of moles = mass in grams / molar mass
- molar mass of H₂O = 2×1.008 g/mol + 15.999 g*mol = 18.015 g/mol
- Number of moles of H₂O = 7.9 g / 18.015 g/mol = 0.439 mol
<u>3) Number of moles of Strontium nitrate dehydrated, Sr (NO₃)₂</u>
- The mass of strontium nitrate dehydrated is the constant mass obtained after heating = 22.9 g
- Molar mass of Sr (NO₃)₂ : 211.63 g/mol (you can obtain it from a internet or calculate using the atomic masses of each element from a periodic table).
- Number of moles of Sr (NO₃)₂ = 22.9 g / 211.63 g/mol = 0.108 mol
<u>4) Ratio</u>
- 0.439 mol H₂O / 0.108 mol Sr(NO₃)₂ ≈ 4 mol H₂O : 1 mol Sr (NO₃)₂
Which means that the hydration number is 4.
Answer:
MECHANISM:
1) The lone pair on oxygen attacks the H-Br molecule forming a hydronium ion.
2) Formation of carbocation.
3) Attack of Nucleophile Br − .
Explanation: