Answer:
Lead sulfite is the inorganic compound with the formula PbSo3 or O3PbS.
Explanation:
Answer:
A) yes
B) The average mass of 12 pennies should be expressed as
( 3.131 + 3.129 + -------- X12 ) g / 12
where X12 = is the mass of the 12th penny
Explanation:
A) I think the the Bureau of Mint changed the way it made pennies because from the experiment and observation carried out on 15 different pennies it can be seen that they had different weights and this difference is associated with the period/time of production of the different pennies,
B ) The average mass of any object should be expressed in the si unit of mass and not having ($) sign attached to the value instead it should be expressed in grams or kilograms (s.i unit of mass )
The average mass of 12 pennies should be expressed as
( 3.131 + 3.129 + -------- X12 ) g / 12
where X12 = is the mass of the 12th penny
Take the attached picture of a periodic table as a guide. You are finding for a solid metal. Therefore, streamline your choices by looking at elements written in black bold letters, because they are all solid. Next, if you look at the center, the legend for metals are colors in orange, yellow, flesh, lavender, pink, and cyan blue. These region would be your choices. Next, you want to find a metal that is shiny and ductile. The shiny appearance is a common characteristic of luster by materials. Ductility is the ability of a metal to stretch when under tensile stress. These properties are best exhibited by metals in the transitions metals colored in pink. Therefore, the answer to your question would be any of the metal in the pink area. Examples are Titanium, Chromium, Gold, Silver, Platinum, Tungsten, etc.
Question #1
Potasium hydroxide (known)
volume used is 25 ml
Molarity (concentration) = 0.150 M
Moles of KOH used
0.150 × 25/1000 = 0.00375 moles
Sulfuric acid (H2SO4)
volume used = 15.0 ml
unknown concentration
The equation for the reaction is
2KOH (aq)+ H2SO4(aq) = K2SO4(aq) + 2H2O(l)
Thus, the Mole ratio of KOH to H2SO4 is 2:1
Therefore, moles of H2SO4 used will be;
0.00375 × 1/2 = 0.001875 moles
Acid (sulfuric acid) concentration
0.001875 moles × 1000/15
= 0.125 M
Question #2
Hydrogen bromide (acid)
Volume used = 30 ml
Concentration is 0.250 M
Moles of HBr used;
0.25 × 30/1000
= 0.0075 moles
Sodium Hydroxide (base)
Volume used 20 ml
Concentration (unknown)
The equation for the reaction is
NaOH + HBr = NaBr + H2O
The mole ratio of NaOH : HBr is 1 : 1
Therefore, moles of NaOH used;
= 0.0075 moles
NaOH concentration will be
= 0.0075 moles × 1000/20
= 0.375 M
