Answer:
you can solve the rest of the equation. I only reduced it to that much to show you how to derive it
Answer:
a)
⇒
⇒
b)
⇒
⇒
Explanation:
A)
Remember that positive number superscripts mean electrons lack and negative numbers mean electrons 'excess' (if we compare it with the neutral element). So, for the case of Fe2+ which is converted to Fe3+, we know that in Fe2+ there is a two electrons lack, while in Fe3+ there is a 3 electrons lack; it means that Fe2+ was converted to Fe3+ but releasing one electron:
⇒
The same analysis is applied to Br2; Br2 is a molecule which is said to have a zero superscript because it is an apolar covalent bond; and it is converted to Br-, which, according to what I wrote above, means that there is a one electron excess. So, Br2 must have received an electron in order to change to Br-; but Br2 can't change to Br- as simple as that because Br2 is a molecule, not an atom; it is a molecule that has two Br atoms, so, Br2 must give two Br- ions as products, but receiving one electron for each one:
⇒
b)
Applying the same, in Mg2+ there is a 2 electrons lack, and in Mg is not electron lack (its superscript is zero), so Mg must have released two electrons in order to change to Mg2+:
⇒
Cr3+ has a 3 electrons lack, and Cr2+ a two electrons one, so, Cr3+ must receive an electron to convert to Cr2+:
⇒
Answer:
Strontium
Explanation:
The atomic number of strontium is 38.
It has 38 electrons.
It is alkaline earth metal. It has two valance electrons.
Strontium loses its two electrons and form cation with +2 charge.
Electronic configuration;
Sr₃₈ = [Kr] 5s²
The valance electrons present in 5s are lost by strontium atom and form Sr⁺² cation.
it is yellowish-white metal.
It is highly reactive.
It form salt with halogens.e.g
Sr + Br₂ → SrBr₂
IT react with oxygen and form oxide.
2Sr + O₂ → 2SrO
this oxide form hydroxide when react with water,
SrO + H₂O → Sr(OH)₂
With nitrogen it produced nitride,
3Sr + N₂ → Sr₃N₂
With acid like HCl,
Sr + 2HCl → SrCl₂ + H₂
The answer is: absorbs more H (protons) ions.
- The Sodium hydroxide NaOH ionizes completely when dissolved in water.
- For every mole of sodium hydroxide that you dissolve you get 1 mole of hydroxide anions.
The heat lost by the metal should be equal to the heat
gained by the water. We know that the heat capacity of water is simply 4.186 J
/ g °C. Therefore:
100 g * 4.186 J / g °C * (31°C – 25.1°C) = 28.2 g * Cp *
(95.2°C - 31°C)
<span>Cp = 1.36 J / g °C</span>