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3 years ago

I need an answer asap

Chemistry

1 answer:

Levart [38]3 years ago

7 0

Scientists can calculate the number of neutrons by subtracting the atomic number from the atomic mass.

they subtract the protons

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Periodic Table Question

natta225 [31]

Bottom left on the periodic table

5 0

3 years ago

A solution contains 3.1 mM Zn(NO3)2 and 4.2 mM Ca(NO3)2. The p-function for Zn2+ is _____, and the p-function for NO3- is _____.

seropon [69]

Answer: The p-function of $Zn^{2+}$ and $NO_3^{-}$ ions are 2.51 and 2.14 respectively.

Explanation:

p-function is defined as the negative logarithm of any concentration.

We are given:

Millimolar concentration of zinc nitrate = 3.1 mM

Millimolar concentration of calcium nitrate = 4.2 mM

Converting this into molar concentration, we use the conversion factor:

1 M = 1000 mM

Concentration of zinc nitrate = 0.0031 M = 0.0031 mol/L

1 mole of zinc nitrate produces 1 mole of zinc ions and 2 moles of nitrate ions

Concentration of zinc ions = 0.0031 M

Concentration of nitrate ions in zinc nitrate, $M_1=(2\times 0.0031)=0.0062M$

Concentration of calcium nitrate = 0.0042 M = 0.0042 mol/L

1 mole of calcium nitrate produces 1 mole of calcium ions and 2 moles of nitrate ions

Concentration of calcium ions = 0.0042 M

Concentration of nitrate ions in calcium nitrate, $M_2=(2\times 0.0042)=0.0084M$

To calculate the concentration of nitrate ions in the solution, we use the equation:

$M=\frac{M_1V_1+M_2V_2}{V_1+V_2}$

Putting values in above equation, we get:

$M=\frac{(0.0062\times 1)+(0.0084\times 1)}{1+1}\\\\M=0.0073M$

Calculating the p-function of zinc ions and nitrate ions in the solution:

For zinc ions:

$\text{p-function of }Zn^{2+}\text{ ions}=-\log[Zn^{2+}]$

$\text{p-function of }Zn^{2+}\text{ ions}=-\log(0.0031)\\\\\text{p-function of }Zn^{2+}\text{ ions}=2.51$

For nitrate ions:

$\text{p-function of }NO_3^{-}\text{ ions}=-\log[NO_3^{-}]$

$\text{p-function of }NO_3^{-}\text{ ions}=-\log(0.0073)\\\\\text{p-function of }NO_3^{-}\text{ ions}=2.14$

Hence, the p-function of $Zn^{2+}$ and $NO_3^{-}$ ions are 2.51 and 2.14 respectively.

5 0

3 years ago

Question 10

eduard

Answer:

C. Biodiesel made from plant oil.

Explanation:

The type of vegetable oil used in production greatly affects the performance of biodiesel in the winter. The less saturated the fat, the better the performance in winter time. Canola oil works very well for low temperature biodiesel, and palm oil is among the worst for cold weather performance.

Hope this helped!!!

5 0

2 years ago

Most geologists think that the movement of Earth's plates is caused by

butalik [34]

Answer: C. Convection currents in the asthenosphere.

Explanation: Most geologists think that the movement of Earth's plates is caused by convection currents in the asthenosphere.

***If you found my answer helpful, please give me the brainliest, please give a nice rating, and the thanks ( heart icon :) ***

7 0

2 years ago

Dermal tissue in plants, is most like what tissue in humans?

Arte-miy333 [17]

The dermal tissue is basically the outer part of the cell that protects the plant cell so in that case it would be the carbohydrate or cell wall. If you would put the choices it could have been a bit better :)

7 0

3 years ago