Answer:
D- They use the exchange rate to convert one's Country's currency to another's
Explanation:
Chemical
bonds between atoms in reactants undergo change during a chemical
reaction.
<span>The substance (or substances) initially involved in a </span>chemical reaction<span> <span>are
called reactants or reagents. </span></span>Chemical reactions<span> <span>are
usually characterized by a </span></span>chemical<span> change,
and they yield one or more products, which usually have properties different
from the reactants.</span>
The correct answer between all
the choices given is the last choice or letter D. I am hoping that this answer
has satisfied your query and it will be able to help you in your endeavor, and
if you would like, feel free to ask another question.
The answer is <span>non-biodegradable and subject to bioaccumulation and/or bioamplification.
DDT (dichlorodiphenyltrichloroethane) is persistent, non-degradable insecticide and organic pollutant readily accumulated to soils and consequently affects organisms.
DDE (</span><span>dichlorodiphenyldichloroethylene) is non-degradable pesticide toxic to birds at the first place.
PCBs (polychlorinated biphenyls) are non-degradable organic compounds very toxic to the environment.
PBDEs (polybrominated diphenyl ethers) are non-degradable compounds very toxic to environment, even able to affect brains of animals in the development period.</span>
<h2>Answer </h2>
Option C - 320J
<u>Explanation </u>
Since ethanol solid at −120 °C and is only cooling down (it won’t change states)
. The amount of Thermodynamic properties values c is given in form of solid, liquid and gas. Amount of energy released is calculated below.
Formula,
= change in temperature x specific heat capacity for solid ethanol x 40
=> 0.5 x 16x 40 = 320J
Therefore, the 320J of heat is released when 40.0g of ethanol cools.
Answer:
Explanation:
a. Oxidation : 2O + 4e^- ------> 2O^2-
b. Reduction: 2Sr - 4e- -------> Sr^2+
c. Balanced redox reaction
2Sr + O2 ------------> 2Sr O
Oxidation and reduction can be defined by various means, addition of oxygen, removal of hydrogen, removal of electrons. For this reaction, this definition is used, oxidation is the loss of electrons while reduction is the gaining of electrons.
In (a) oxidation half reaction, the valency of oxygen is zero and then moves into lossing two electrons resulting into -2 valency.
In (b) reduction half reaction, the valency of Sr is zero and gains electrons resulting into valency of 2.
In the overall redox reaction, Sr and O2 with valency of 0 each reacts together and form SrO with valency of 2 and -2 respectively, which gives 0 and then balances the equation.
