Answer:
This is a precipitation reaction in which Ni(OH)₂ precipitates.
8.68%
Explanation:
Let's consider the following reaction.
Ni²⁺(aq) + 2 NaOH(aq) ⇄ Ni(OH)₂(s) + 2 Na⁺(aq)
This is a precipitation reaction in which Ni(OH)₂ precipitates.
We can establish the following relations:
- The molar mass of Ni(OH)₂ is 92.71 g/mol.
- 1 mole of Ni(OH)₂ is produced per 1 mole of Ni²⁺.
- The molar mass of Ni²⁺ is 58.69 g/mol.
When 343 mg (0.343 g) of Ni(OH)₂ are collected, the mass of Ni²⁺ that reacted is:

The mass percent of nickel in the 25.0g-sample is:

Answer:

Explanation:
There are two main kinds of properties: chemical and physical.
Chemical properties, like the name suggests, have to be observed by changing the chemical composition.
That leaves <u>physical properties.</u> They can be measured without any chemical composition changes.
Some examples include: color, odor, mass, density, and volume. All can be measured with just the senses or measuring tools and no composition alterations are needed.
Q unknown = -Q H2O
Q H2O= (100g x 4.18 J/g C x (25C - 20C)
Q H2O = 2090J
-2090J = (50g x c x (25C-90C)
-2090J = -3250c
.64 = c
I am a high school student and have done this problem a few months ago for my test, hope this helps
Answer:
(2) Organelles must work together and their
activities must be coordinated
Explanation:
Organelles are usually located in cells. They are saddled with the role of performing specific functions in the cells for the overall functioning of life. In eukaryotic cells, the organelles are membrane bounded but in prokaryotic or primitive cells such is not the case.
Examples of cell organelles are ribosome, food vacuole, nucleus e.t.c. Just like organs in the body, organelles must work together in order to enhance life.
Answer:
25.157 cm³
Explanation:
Data Given:
Mass of Sugar (m) = 40g
Density of sugar given in literature = 1.59 g/cm³
Volume of Sugar = ?
The formula will be used is
d = m/v ........................................... (1)
where
D is density
m is the mass
v is the volume
So
Rearrange the Equation (1)
d x v = m
v = m/ d ................................................ (2)
put the given values in Equation (2)
v = 40g / 1.59 g/cm³
v = 25.157 cm³
volume of 40 g of sugar = 25.157 cm³