Answer:
<h2>12.1 </h2>
Explanation:
Since the pH has been given, the pOH can be found by using the formula
pH + pOH = 14
pOH = 14 - pH
From the question we have
pOH = 14 - 1.9
We have the final answer as
<h3>12.1</h3>
Hope this helps you
It isn't a materialistic object.
Answer:
Zn, Cu, Fe, Mn, Co, Mo
Explanation:
Biogenic elements are chemical elements constantly present in organisms and having definite biological significance(Bowen, 1966).
There are many of these biogenic elements in nature. Among the elements of the d-block, Zn, Cu, Fe, Mn, Co, Mo are worthy of mention among others.
Free ions of d- block metals are not found in the body. The elements are present in the form of bioinorganic complexes of the respective metals. They commonly exist as co-factors of proteins that carry out essential biological functions.
True.
For example: Sodium oxide and Nitric acid; both compounds contain oxygen.
Answer:
526g is the mass of this sample
Explanation:
To solve this question we must, as first, find the <em>molar mass </em>of Al₂(Cr₂O₇)₃ using the periodic table. The molar mass is defined as the mass of this compound per mole. With this value we can find the mass in 0.750 moles as follows:
<em>Molar mass Al₂(Cr₂O₇)₃</em>
2Al = 2*26.98g/mol = 53.96g/mol
6 Cr = 6*51.9961g/mol = 311.9766g/mol
21 O = 21*15.999g/mol = 335.979g/mol
53.96g/mol + 311.9766g/mol + 335.979g/mol
= 701.9156g/mol
The mass of 0.750 moles is:
0.750 moles * (701.9156g / mol) =
<h3>526g is the mass of this sample</h3>
