The answer is B. Boron
The number of electrons and protons are always the same in an atom.
There are 5 electrons which means there are also 5 protons.
The number of Protons determines the atomic number of an element.
Since the element has 5 protons its atomic number is 5, the same atomic number as Boron
Answer:
41.4%
Explanation:
The salt copper II fluoride tetrahydrate is a hydrated salt. A hydrated salt is a salt that has some molecules of water of crystalization attached to its structure. The formula of the salt is CuF2.4H2O
The first step is to calculate the molecular mass of the compound as follows
[64 + 2(19) + 4((2×1) + 16)] = [64 + 38 + 72]= 174gmol-1
Mass of water of crystallization= 4((2×1) + 16) = 72 g
Percentage by mass of water of crystallization= 72 / 174 ×100
Percentage by mass of water if crystalization = 41.4%
The answer is C. One item replacing another is a single replacement, but when two items trade places in two separate molecules it’s double replacement.
Answer:
C. Speed
Explanation:
Density differences in different materials are able to change the speed of a wave.
- Wave speed is dependent on the frequency and wavelength of a wave.
- As a wave travels from one medium to another, the speed of the wave changes.
- Speed of a wave is medium dependent.
- The denser a medium, the slower the speed of waves will be be.
- A less dense medium will have waves traveling through faster.
Answer:
The volume is
<h2>180 mL</h2>
Explanation:
In order to solve for the volume we use the formula for Boyle's law which is
<h3>
</h3>
where
P1 is the initial pressure
V1 is the initial volume
P2 is the final pressure
V2 is the final volume
Since we are finding the final volume we are finding V2
Making V2 the subject we have
<h3>
</h3>
From the question
P1 = 300 mmHg
V1 = 300 mL
P2 = 500 mmHg
Substitute the values into the above formula and solve for the final volume obtained
That's
<h3>
</h3>
We have the final answer as
<h3>180 mL</h3>
Hope this helps you
