Answer:A
Explanation:
In the Biuret test, the copper ions bind covalently to the amino groups as shown in the image to form a violet complex. This violet complex is responsible for the colour change as shown
If the element have 39 protons, that means that his atomic number is 39, being Yttrium the element. And, the number of protons is the same of the number of electrons, so, 39 electrons.
C6H15, C2H5 has a molar mass of 29g/mol. 87 divided by 29 is 3. Then multiply each element subscript by 3
6.7 mass because 1 atom equals 6.3 but if u add 4 it would be 6.7
The molar concentration is 1.11M.
<h3>What is molar concentration?</h3>
The phrase "molar concentration" (also known as "molarity," "amount concentration," or "substance concentration") refers to the amount of a substance per unit volume of solution and is used to describe the concentration of a chemical species, specifically a solute, in a solution. The most frequent measure of molarity in chemistry is the number of moles per liter, denoted by the unit symbol mol/L or mol/dm3 in SI units. A solution with a concentration of 1 mol/L is referred to as 1 molar, or 1 M.
<h3>Given : </h3>
Volume of the solution = 2L
Mass of glucose given = 200g
Concentration of glucose= ?
<h3>Formula use: </h3>
Molarity = no. of moles of solute / volume of the solution (L)
Moles of solute = given mass of solute / molar mass of the solute
<h3>Solution: </h3>
No. of moles of solute( glucose ) = 200 / 180 = 1.11 moles'
Molarity = 1.11 / 2 = 0.5555 mol L ^(-1)
Therefore, the molar concentration of glucose in the solution = 0.555 mol L ^(-1)
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