Answer is: -601,2 kJ/mol
Chemical reaction: Mg(OH)₂ → MgO + H₂O.
ΔHrxn = 37,5 kJ/mol.
ΔHf(Mg(OH)₂) = <span>−924,5 kJ/mol.
</span>ΔHf(H₂O) = <span>−285,8 kJ/mol.
</span>ΔHrxn -enthalpy of reaction.
ΔHf - enthalpy of formation.
<span>ΔHrxn=∑productsΔHf−∑reactantsΔHf.
</span>ΔHf(MgO) = -924,5 kJ/mol - (-285,8 kJ/mol) + 37,5 kj/mol.
ΔHf(MgO) = -601,2 kJ/mol.
Answer:
Explanation:
3. The number of electrons and neutrons in an atom are 13 and 14, respectively. Find out the mass number, atomic number, valency, and symbol of the element.
For a neutral atom. number of protons =number of electrons=13
so since atomic number is the number of protons =13
mass number = protons + neutons =14+13 = 27
atomic number 13 is Aluminum (AL-(see periodic table)
The electronic structure for 13 electrons is 1s2s2p63s23p1
so Al has 3 electrons which are VALIENT and can react and when it loses the 3 it will have CHARGE OF +3
Given:
Stock dose/concentration of 20% Acetylcysteine (200 mg/mL)
150 mg/kg dose of Acetylcysteine
Weight of the dog is 13.2 lb
First we must convert 13.2 lb to kg:
13.2 lb/(2.2kg/lb) = 6 kg
Then we must calculate the dose:
(150 mg/kg)(6kg) = 900 mg
Lastly, we must calculate the dose in liquid form to be administered:
(900 mg)/(200 mg/mL) = 4.5 mL
Therefore, 4.5 mL of 20% Acetylcysteine should be given.
Answer:
The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons.
Explanation: