V = displacement /time
= 3/3 = 1km/hr
Answer:
an exposure to a virus is actually having the virus and developing an immunity to a virus is similar because to be immune to a virus you have to receive a vaccine and a vaccine is actually the disease injecting into your system in a different way so when the virus attacks you your body cells know what to do to fight the disease.
Explanation:
Answer:
closer to F because fluorine has a higher electronegativity than carbon
Explanation:
Electronegativity refers to the ability of an atom in a bonding situation to draw the shared electrons of the bond closer to itself.
Electronegativity increases across the period and decreases down the group. A highly electronegative atom draws the shared electron pair of a bond towards itself.
When two atoms are bonded together, the electron pair is always drawn closer to the atom that has a higher electronegativity.
Hence, the electron pair in a C-F bond could be considered closer to F because fluorine has a higher electronegativity than carbon.
Answer:
A. 29.9
Explanation:
- An element can have differing numbers of neutrons in its nucleus, but it always has the same number of protons. The versions of an element with different neutrons have different masses and are called isotopes.
- The average atomic mass for an element is calculated by summing the masses of the element’s isotopes, each multiplied by its natural abundance on Earth.
<em>Average atomic mass of P = ∑(Isotope mass)(its abundance)</em>
∴ Average atomic mass of P = (P-29 mass)(its abundance) + (P-30 mass)(its abundance) + (P-31 mass)(its abundance) + (P-33 mass)(its abundance)
<em>Abundance of isotope = % of the isotope / 100.</em>
<em>∴ Average atomic mass of P =</em> (29)(0.327) + (30)(0.4803) + (31)(0.184) + (33)(0.0087) = <em>29.88 a.m.u ≅ 29.9 a.m.u.</em>
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<em>So, the right choice is: A. 29.9</em>
