Answer:-A. It is less than 890 kJ/mol because the amount of energy required to break bonds is less than the amount of energy released in forming bonds.
Explanation: Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and 
for the reaction comes out to be positive.
Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and for the reaction comes out to be negative.
In the formation of new bonds more energy is released than is required to break the existing bonds, heat is released.
In the formation of bonds less energy is released than is required to break the existing bonds, heat is absorbed.
N = 1
l = from 0 to (n-1)
ml = -1... + 1
ms = 1/2 or -1/2
eg = 2s
n = 2, m = 0, n = 0
s = 1/2, -1/2
hope this help
Answer:
Adding a solution containing an anion that forms an insoluble salt with only one of the metal ions.
Explanation:
The student have in solution Ag⁺ and Cu²⁺ ions but he just want to analyze the silver, that means he need to separate ions.
Centrifuging the solution to isolate the heavier ions <em>FALSE </em>Centrifugation allows the separation of a suspension but Ag⁺ and Cu²⁺ are both soluble in water.
Adding enough base solution to bring the pH up to 7.0 <em>FALSE </em>At pH = 7,0 these ions are soluble in water and its separation will not be possible.
Adding a solution containing an anion that forms an insoluble salt with only one of the metal ions <em>TRUE </em>For example, the addition of Cl⁻ will precipitate the Ag⁺ as AgCl(s) allowing its separation.
Evaporating the solution to recover the dissolved nitrates. <em>FALSE</em> . Thus, you will obtain the nitrates of these ions but will be mixed doing impossible its separation.
I hope it helps!
With reference to present question, following things may be noted
1) Oxidation is process of lose of electron. Atom//ion undergoing oxidation is refereed as reducing agent
2) Reduction is process of gain of electron. Atom/ion undergoing reduction is refereed as oxidizing agent.
in present system, Ag+ gain an electron to reduced to Ag. Therefore, Ag+ is an oxidizing agent.
Answer:
The correct option is D.
Explanation:
Radioactive substances usually emit different types of particles when they are decaying. Such particles include alpha particles, beta particles and gamma ray. When an alpha particle is emitted from an unstable radioactive nucleus such nucleus usually lost an atomic mass that correspond to that of helium atom. Note that an alpha particle is made up of two protons and two neutrons, which result in mass number of 4. Thus, a nucleus that emit an alpha particle will have its mass number (atomic mass) reduce by 4 and atomic number that is reduced by 2.
