Carbohydrates are biological molecules made of carbon, hydrogen, and oxygen in a ratio of roughly one carbon atom (
C
Cstart text, C, end text) to one water molecule (
H
2
O
H
2
Ostart text, H, end text, start subscript, 2, end subscript, start text, O, end text). This composition gives carbohydrates their name: they are made up of carbon (carbo-) plus water (-hydrate). Carbohydrate chains come in different lengths, and biologically important carbohydrates belong to three categories: monosaccharides, disaccharides, and polysaccharides.
Answer:
All the option are correct
Explanation:
The ocean currents have been associated with past climatic shifts during critical periods (for example, the ice ages), where modifications in water circulation might have caused important climatic changes.
From a biological point of view, the ocean currents may be associated not only with the climate but also biogeochemical cycles through modifications in the distribution of heat and freshwater. Thus, the changes in ocean circulation may produce biogeographical shifts by affecting the local climate. The importance of ocean currents in affecting biodiversity is also represented by the equilibrium of coral reef ecosystems, where this equilibrium is broken up by factors such as transport of pollutants, temperature conditions, etc., which are known to alter thermosensitive coral species.
Answer:
Explanation:
Let us look at all the answers definitions,
Sponsor would not work as it talks about a company offering you something in back for an advertisement.
Obtain would work as it means to acquire something.
Neglect would not work because it means to fail to care for something properly
Dismiss wouldn't work because it means to leave or allow to exit
Answer:
- <u><em>It is positive when the bonds of the product store more energy than those of the reactants.</em></u>
Explanation:
The <em>standard enthalpy of formation</em>, <em>ΔHf</em>, is defined as the energy required to form 1 mole of a substance from its contituent elements under standard conditions of pressure and temperature.
Then, per defintion, when the elements are already at their standard states, there is not energy involved to form them from that very state; this is, the standard enthalpy of formation of the elements in their standard states is zero.
It is not zero for the compounds in its standard state, because energy should be released or absorbed to form the compounds from their consituent elements. Thus, the first choice is false.
When the bonds of the products store more energy than the those of the reactants, the difference is:
- ΔHf = ΔHf products - ΔHf reactants > 0, meaning that ΔHf is positive. Hence, the second statement is true.
Third is false because forming the compounds may require to use (absorb) or release (produce) energy, which means that ΔHf could be positive or negative.
Fourth statement is false, because the standard state of many elements is not liquid. For example, it is required to supply energy to iron to make it liquid. Thus, the enthalpy of formation of iron in liquid state is not zero.
