Valency is the number of electrons lost or gained by an atom to attain an stable configuration. Valency is important when writing the formula of chemical compounds in chemistry. Strontium has a valency of 2 while sulfite ion (radicle) has a valency of 2. Therefore, the chemical formula of strontium sulfite is written as SrSO3.
Answer:
C. Mutations are a change in DNA or a chromosome and can be helpful, harmful or may have no affect.
Explanation:
- Mutations are spontaneous random changes that occurs in the genetic make up of an organisms. Mutations are rare and their rate of occurrence is random.
- Mutations may occur on the gene level known as gene mutations or at chromosome levels called chromosomal mutations.
- Mutations may be beneficial, harmful or have no effect on a given organisms. Harmful mutations cause disorders that may lead to abnormality or death of an organisms. Beneficial mutations improve an organisms adaptability to the environment.
The products. Without a balanced chemical equation, there is no reaction that can take place. The products is the final reation and the reactants help the final reaction take place.
<u>Answer:</u> The for the reaction is 72 kJ.
<u>Explanation:</u>
Hess’s law of constant heat summation states that the amount of heat absorbed or evolved in a given chemical equation remains the same whether the process occurs in one step or several steps.
According to this law, the chemical equation is treated as ordinary algebraic expressions and can be added or subtracted to yield the required equation. This means that the enthalpy change of the overall reaction is equal to the sum of the enthalpy changes of the intermediate reactions.
The given chemical reaction follows:
The intermediate balanced chemical reaction are:
(1)
(2) ( × 2)
(3) ( × 2)
The expression for enthalpy of the reaction follows:
Putting values in above equation, we get:
Hence, the for the reaction is 72 kJ.
Answer:
A
Explanation:
Hmm, so we have the following in the diagram
Pt(s)
Cl2(g)
Ag(s)
NaCl(aq)
AgNO3(aq)
Pt 2+, 4+, 6+ Though it states Pt is inert
Cl 2-
Ag 1+
Na 1+
NO3-
Anode definition: the positively charged electrode by which the electrons leave an electrical device.
Electrode definition: a conductor through which electricity enters or leaves an object, substance, or region.
Cations attracted to cathode pick up electrons
Anions attracted to anode release electrodes+
Reduction at Cathode (red cat gain of e)
Oxidation at Anode (ox anode loss of e)
So from the diagram we can see that the charge is being generated through the 2 metal plates.
So the answer is A, the anode material is Pt and the half reaction is 2Cl- = Cl2 + 2e-