Answer:
B. observing that a bone placed in a beaker of acid becomes bendy
Explanation:
The hypothesis suggests that when chicken bones are placed in vinegar, they become bendy due to the loss of calcium in their bones.
Calcium is identified as the ossifying material that strengthens the bone. When the acid that makes up the vinegar comes in contact with it, calcium is removed from the bone.
Now we know that calcium has capabilities of reacting with acids.
This suggests that if we also place the bone in an acid, they will bend due to reaction of calcium in the bones with the acid.
MnO₂(s) + 4 HCl(aq)→ MnCl₂(aq) + 2 H₂O(l) + Cl₂(g)
<u>Explanation:</u>
When aqueous solution of hydrochloric acid (HCl) reacts with solid Manganese(IV)oxide to form manganese(II)chloride in aqueous form, liquid water and then chlorine gas. The equation is given as,
MnO₂(s) + HCl(aq)→ MnCl₂(aq) + H₂O(l) + Cl₂(g)
It can be balanced by writing 2 in front of water and then writing 4 in front of HCl as,
MnO₂(s) + 4 HCl(aq)→ MnCl₂(aq) + 2 H₂O(l) + Cl₂(g)
So the balanced equation was found.
How to Tell Lewis Diagrams apart
Trigonal planar, Trigonal pyramid both have 3 things attached to them. Not 4. Tetrahedral is the only Lewis Diagram's center piece that has 4 things attached to it.
<em><u>Tetrahedral</u></em>: C with 4 Cl's attached.
<em><u>Trigonal Planar</u></em>: is flat. The element in the middle is generally a metal or an element from the Left side of the periodic table. There is never an isolated pair of electrons with Trigonal Planer shapes. Summary:
- The center element is a Metal on the left side of the periodic table.
- In your example, Boron is at the center of the drawing and it is in column 2 of the periodic table which makes it a metal.
- There are no isolated electron pairs
Trigonal Pyramid
- The two electrons are circled. These two are isolated and nothing is attacted to them.
- The central element is a non metal -- Nitrogen in this case.
- The non metal is on the RIGHT side of the periodic table
Bent
- Looks like it is in a straight line (but it is not).
- There are usually double bonds involved.
- The angle formed is usually greater than 90 degrees
- The central element is usually a non metal.
Problem One
Both parts of this question are correct.
Answer:
50 mL
Explanation:
In case of titration , the following formula is used -
M₁V₁ = M₂V₂
where ,
M₁ = concentration of acid ,
V₁ = volume of acid ,
M₂ = concentration of base,
V₂ = volume of base .
from , the question ,
M₁ = 0.50M
V₁ = 100 mL
M₂ = 1.0M
V₂ = ?
Using the above formula , the volume of base , can be calculated as ,
M₁V₁ = M₂V₂
substituting the respective values ,
0.50M * 100 mL = 1.0M * V₂
V₂ = 50 mL