Answer:
Chemical
Explanation:
Macromolecules are part of the chemical components of cells. For example, DNA, proteins, and lipids.
Cells of similar types/function form tissues. Different types of tissues interact together to form organs. Organs form a common function.
Answer:Two more hydrogen atoms will be required
Explanation:
A carbon atom has 4 valence electrons in its outermost shell,thus it can form 4 covalent bonds.Two pairs of electrons are shared in a double bond between C-C atom.two more electrons are left which is shared with two hydrogen atoms.
Answer:
Option B is correct. A nuclear alpha decay
Explanation:
Step 1
This equation is a nuclear reaction. So it can be an alpha decay or a beta decay
An α-particle is a helium nucleus. It contains 2 protons and 2 neutrons, for a mass number of 4.
During α-decay, an atomic nucleus emits an alpha particle. It transforms (or decays) into an atom with an atomic number 2 less and a mass number 4 less.
Thus, radium-226 decays through α-particle emission to form radon-222 according to the equation that is showed.
A Beta decay occurs when, in a nucleus with too many protons or too many neutrons, one of the protons or neutrons is transformed into the other.
Option B is correct. A nuclear alpha decay
<span>40 20Ca this is the appropriate symbol for an isotope of calcium-42 corresponding to the isotope notation AZX</span><span />
43.8 kJ
<h3>
Explanation</h3>
There are two electrodes in a voltaic cell. Which one is the anode?
The lithium atom used to have no oxygen atoms when it was on the reactant side. It gains two oxygen atoms after the reaction. It has gained more oxygen atoms than the manganese atom. Gaining oxygen is oxidation. As a result, lithium is being oxidized.
Oxidation takes place at the anode of a cell. Therefore, the anode of this cell is made of lithium.
Lithium has an atomic mass of 6.94. Each gram of Li would contain 1/6.94 = 0.144 moles of Li atoms. Each Li atom loses one electron in this cell. Therefore, the number of electron transferred, <em>n</em>, equals 0.144 moles for each gram of the anode.
Let 
represents the electrical energy produced.
, where
- <em>n</em> is the <em>number of moles</em> electrons transferred,
- <em>F</em> is the Faraday's constant,
- <em>E</em>
is the cell potential,
<em>n </em>= 0.144 mol, as shown above, and
<em>F </em>= 96.486 kJ / (
).
Therefore,
.
