Answer:
Iron has 5 unpaired electrons in Fe⁺³ state.
Explanation:
Iron having atomic number 26 has following electronic configuration in neutral state.
Fe = 1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d⁶
When Iron looses three electrons it attains +3 charge with following electronic configuration.
Fe⁺³ = 1s², 2s², 2p⁶, 3s², 3p⁶, 3d⁵
The five electrons in d-orbital exist in unpaired form as,
3(dz)¹, 3d(xz)¹, 3d(yz)¹, 3d(xy)¹, 3(dx²-y²)¹
Decay is a type of degradation reaction and thus is considered a first order reaction. thus the formula goes like this.
rate constant= 0.693/half life
so here...
rate constant= 0.693/1620 year^-1
Answer : The correct option is, (C) 10-mL volumeric pipet.
Explanation :
Graduated cylinder : It is a measuring cylinder that is used to measure the volume of a liquid. It has a narrow cylindrical shape. The marked line drawn on the graduated cylinder shows the amount of liquid that has been measured.
Pipet : It is a type of laboratory equipment that is used to measure the volume of a liquid. It is small glass tube and the marked line drawn on the pipet. It is used to accurately measure and transfer of volume of liquid from one container to another.
Volumetric flask : It is a type of laboratory tool that is also used for measuring the volume of liquid. It is used to make up a solution to a known volume. It measure volumes much more precisely than beakers.
Beaker : It is a type of laboratory equipment that has cylindrical shape and it is used for the mixing, stirring, and heating of chemicals.
As per question, we conclude that the pipet is most precise than other devices because in pipet the marking lines are more accurate. Thus, it can be used to measure volume to precision.
Hence, the correct option is, (C) 10-mL volumeric pipet.
Answer:
that is all I know sorry hope that may help you :)
Explanation:
Indicator is a substance which shows different colors in acidic and basic medium. Indicators can be natural (derived from natural sources) or artificial ( man-made) for example :
*Litmus is an indicator. Acid turns blue litmus into red while base turns red litmus into blue
* Turmeric solution does not show change in color (remains yellow) in acidic solution and turns red in basic solution.
Answer:
The total mass of D-Glucose dissolved in a 2μL aliquot is 1 E-4 g
Explanation:
providing a solution to 5% weight-volume as found in commerce:
⇒ % 5 = (5g d-glucose/ 100 mL sln)×100
⇒ 0.05 = g C6H12O6/mL sln
⇒ g C6H12O6 = (2 μL sln)×(0.001 mL/μL)×(0.05 g C6H12O6/mL sln)
⇒ g C6H12O6 = 1 E-4 g C6H12O6
