Answer:
c) Wash your hands
Explanation:
A laboratory or most popularly called as lab is a place or facility which provides controlled conditions where some educational research, scientific studies, experiments, testings, can be performed. The place is equipped with sophisticated machines, test samples, hazardous chemicals, instruments etc.
The university or college lab, there is a incharge of the lab called as the lab instructor who is responsible for all the belongings of the lab and the safety of the experimenter or the students.
After performing some experiments or testing with some chemicals, the last and the most important thing we need to do is to wash our hand with soap or hand wash. it is very important because we touch many test samples and hazardous chemical which might go inside our mouth or eyes accidentally, which might be harmful to us.
So, it is important to wash our hand at last before leaving the lab.
Answer:
a) 2-bromopyrrole
Explanation:
Our options for this questions are:
a) 2-bromopyrrole
b) 2,3-dibromopyrrole
c) N-bromopyrrole
d) 3-bromopyrrole
To understand how the reaction works we have to start with the <u>resonance structures</u>. (Figure 1), on these structures, we will obtain a n<u>egative charge on carbon 2</u> in the pyrrole ring, therefore on this carbon we can generate an attack to an electrophile.
The second step is to check how the mechanism take place. An <u>electrophile is generated</u> by the 
and 
. This electrophile can be <u>attacked</u> by the negative charge on carbon 2 producing the 2-bromopyrrole. (See figure 2).
I hope it helps!
Answer:
1.5×10⁷ Hz
Explanation:
From the question given above, the following data were obtained:
Wavelength of radio wave (λ) = 20 m
Frequency (f) =?
Frequency and wavelength of a wave are related by the following equation:
v = λf
Where:
'v' is the velocity of electromagnetic wave.
'λ' is the wavelength
'f' is the frequency.
With the above formula, we can obtain the frequency of the radio wave as illustrated below:
Wavelength of radio wave (λ) = 20 m
Velocity (v) = 3×10⁸ m/s
Frequency (f) =?
v = λf
3×10⁸ = 20 × f
Divide both side by 20
f = 3×10⁸ / 20
f = 1.5×10⁷ Hz
Thus the frequency of the radio wave is 1.5×10⁷ Hz
Note that the density of pure aluminum is 2.7 g/cm³ (from tables).
Given:
m = 39.0 g, the mass of the metal
V = 10.0 cm³, the density of the metal
By definition, the density of the metal is
density = mass/volume
= (39.0 g)/(10.0 cm³)
= 3.9 g/cm³
Answer:
The calculated density is not equal to 2.7 g/cm³, therefore the metal sphere is not made of pure aluminum.
invisable
you probably dont want to put that...
