Buffers - mixtures of conjugate acid and conjugate base at ±1 pH unit from pH = pKa. Resistant to changes in pH in response to small additions of H+ or OH-. ... Polyprotic acids - dissociation of each H+ can be treated separately if the pKa values are different
When the volume is 450 cm3 so the boat will displace 450 g.
so we have 450 g - 14.5g = 435.5 left
so to get how many pennies can be added to the boat before it sinks can be determined by:
divided the mass for the one penny:
no.of Penny = 435.5 / 2.5g
= 174.2
∴ the boat will float with 174 pennies and will start to sink with 175
1)
-Lithium: Lithium got 3 protons, so it atomic number is 3. It is located on the first column of the periodic table, and belonging to the alkali metal. So lithium is a metal. Lithium is highly reactive.
-Neon: It is located on the 18th column of the periodic table, and belong to the noble gases. So Neon is a nonmetal. Neon's reactivity is very low.
-Fluorine: Located on the 17th column of the periodic metal, fluorine is a nonmetal, and belong to the halogen family. Fluorine's reactivity is high.
2)
-Vertical columns of the periodic table are called columns. There is 18 column in the periodic table, and each one represent a chemical family.
-Horizontal rows of the periodic table care called periods. There is 7 periods in the periodic table.
-The number of protons in an atom is that element's atomic number. And since the atom is electrically neutral, the number of protons is equal to the number of electrons. So if you have the number of electrons, you can still find the atomic number.
-The total of protons and neutrons in an atom is that element's atomic mass. Based on the formula A = Z + N, where A represents the atomic mass, Z the atomic number (number of protons) and N the number of neutrons.
-The elements in group 1 are the most reactive metals. This group is called the Alkali metals. They only have 1 electron in their outer shell which makes them always ready to lose an electron in an ionic bonding.
-The elements in group 17 are the most reactive nonmetals. This group is called the Halogens, with 7 electrons in their outer shell which makes them always ready to win an electron in an ionic bonding.
-The elements in group 18 are the most unreactive elements. This group is called the Noble gases. Their outer shell is always full, so it can't do reactions.
Hope this Helps! :)
<span>He should use a scale and record the weight in N. The beaker is used for liquid measurement and the scale is used for measuring sold things. A dumbbell is not a liquid material that is why the need of the scale will give it the accurate measurement that Hunter wants to know.</span>