Answer:Small-scale technique means a small quantity of chemicals that contribute to the safety of the experiments. Instead of using big beaker of chemical, micro scale technique utilize small quantities of chemical and scaled-down science equipment.
Explanation:
Generally speaking, organic molecules tend to dissolve in solvents that have similar physical properties. A good rule of thumb is that "like dissolves like". Meaning, polar compounds can dissolve polar compounds and nonpolar compounds can dissolve nonpolar compounds.
To apply this to the current problem, we are told that the brushes are being cleaned with vegetable oil or mineral oil. In this case, the oils are used as solvents. In order for these solvents to be effective, the compounds they are trying to dissolve must be similar in structure and properties to other oils. Therefore, vegetable oil or mineral oil will be most effective in removing oil-based paints, as these will have the similar properties needed to dissolve in the oil solvents.
Answer:- 0.138 M
Solution:- The buffer pH is calculated using Handerson equation:

acts as a weak acid and
as a base which is pretty conjugate base of the weak acid we have.
The acid hase two protons(hydrogen) where as the base has only one proton. So, we could write the equation as:

Phosphoric acid gives protons in three steps. So, the above equation is the second step as the acid has only two protons and the base has one proton.
So, we will use the second pKa value. The acid concentration is given as 0.10 M and we are asked to calculate the concentration of the base to make a buffer of exactly pH 7.00.
Let's plug in the values in the equation:



Taking antilog:


On cross multiply:
[base] = 1.38(0.10)
[base] = 0.138
So, the concentration of the base that is
required to make the buffer is 0.138M.
<span>We can use
the heat equation,
Q = mcΔT </span>
<span>Where Q is
the amount of energy transferred (J), m is the mass of the substance
(kg), c is
the specific heat (J g</span>⁻¹ °C⁻<span>¹) and ΔT is
the temperature difference (°C).</span>
Let's assume that the finale temperature is T.
Q = 1200 J
<span>
m = 36 g
c = 4.186 J/g °C</span>
ΔT = (T -
22)
By applying
the formula,
1200 J = 36 g
x 4.186 J/g °C x (T - 22)
(T - 22) = 1200 J / (36 g x 4.186 J/g °C)
(T - 22) = 7.96 °C
T = (7.96 + 22) °C = 29.96 °C
T = 30 °C
Hence,
the final temperature is 30 °C.
Answer is: Benzene is trigonal (or triangular) planar.
VSEPR theory (The Valence Shell Electron Pair Repulsion Theory) uses the AXE notation (m and n are integers, m + n = number of regions of electron density).
For benzene molecule (C₆H₆):
m = 3; the number of atoms bonded to the central atom.
n = 0; the number of lone pairs on the central atom.