The answer will be 180.156 g/mol
Answer:
The Retention factor (rf) value is = 0.2
Explanation:
- Retention factor (Rf) is factor used substances that could be separated using Chromatography. Retention factor determines how fast the component can move on the chromatogram (stationary phase) after elution. Elution occurs when mobile phase (solvent) moves across the stationary phase when the solute has been spotted on the origin.
- Retention factor (Rf) ranges from value between 0 and 1. The closer the value to 1, the faster it can move upon elution. Rf can be calculated.
- Rf value = distance moved by the solute / distance moved by the solvent
= 0.40cm / 2.00cm
= 0.2
Answer:
Rubidium (Rb).
Explanation:
From the question given above, the following data were obtained:
Electronic configuration => 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s¹
Name of element =?
To know the name of the element with the above electronic configuration, we shall determine the atomic number of the element. This can be obtained as follow:
Number of electrons = 2 + 2 + 6 + 2 + 6 + 2 + 10 + 6 + 1
Number of electrons = 37
Next, we shall determine the number of protons. This can be obtained as follow:
From the question given above, the element has no charge. Hence the element contains equal numbers of protons and electrons.
Number of electrons = 37
Number of protons = number of electrons = 37
Next, we shall determine the atomic number. This can be obtained as follow:
The atomic number of an element is simply defined as the number of protons present in the atom of the element. Thus,
Atomic number = proton number
Proton is = 37
Therefore,
Atomic number = 37
Finally, we shall determine the name of the element by comparing the atomic number of those in the periodic table.
Thus, the element with the above electronic configuration is Rubidium (Rb) since no two elements have the same atomic number
Answer:
C
Explanation:
A fuel cell uses both hydrogen and oxygen as fuels. At the cathode oxygen is reduced to water according to the equation
O2+4H^+ +4e ------>2H2O
And hydrogen is oxidized at the anode:
2H2------>4H^+ +4e
Fuel cells produce only water as a by product hence they are environment friendly
<span>It is known
that acids compounds contains hydrogen and produces hydrogen ion in water. A binary
acid however is an acid that have two elements, one of the element has a
hydrogen attached to it. Examples of binary acids are hydrogen fluoride (HF),
hydrogen bromide (HBr) and hydrogen sulfide (H2S). In naming a binary acid, it
has two rules; one, as pure compounds and two, as acid solutions. For pure
compounds, start with the name ‘hydrogen’ and end the anion name with ‘-ide’. For
acidic compounds, start with ‘hydro-‘, end the anion with ‘-ic’ and add ‘acid’.</span>