Answer:
Speed, v = 5 m/s
Explanation:
The length of the football field, l = 100 m
the person takes 20 seconds to run its length
v=
t
d
v=
20 s
100 m
v=5 m/s
<span>8.278 g/mL
The definition of density is mass per volume. So what you need to do is divide the known mass by the known volume. So
1.663 g / 0.2009 mL = 8.27775 g/mL
But you also have to keep track of significant figures. Since both 1.663 and 0.2009 have 4 significant figures each, you need to round the result to 4 significant figures. So
8.27775 g/mL = 8.278 g/mL</span>
Ca-Cl is an ionic bond. We know this because the difference between their electronegativities is 2.16.The electronegativity tells us which atom will attract the electron more than the other. Hence, chlorine attracts the electron a lot more than the calcium.A difference of more than 1.6 (or 1.7 depending on the source) implies that the electrons are so unevenly shared, that the bond is ionic, rather than polar covalent.
The answer is protons and electrons! Hope this helps :D
Answer:
10−8 M.
Explanation:
In this problem we are given pH and asked to solve for the hydrogen ion concentration. Using the equation, pH = − log [H+] , we can solve for [H+] as,
− pH = log [H+] ,
[H+] = 10−pH,
by exponentiating both sides with base 10 to "undo" the common logarithm. The hydrogen ion concentration of blood with pH 7.4 is,
[H+] = 10−7.4 ≈ 0.0000040 = 4.0 × In this problem we are given pH and asked to solve for the hydrogen ion concentration. Using the equation, pH = − log [H+] , we can solve for [H+] as,
− pH = log [H+] ,
[H+] = 10−pH,
by exponentiating both sides with base 10 to "undo" the common logarithm. The hydrogen ion concentration of blood with pH 7.4 is,
[H+] = 10−7.4 ≈ 0.0000040 = 4.0 × 10−8 M.
