Which is not a part of the Nervous System?

Write the isotopic symbol for the following (show your work) a) An isotope of iodine whose atoms have 78 neutrons b) An isotope

morpeh [17]

Answer:

For a: The isotopic representation of iodine is $_{53}^{131}\textrm{I}$

For b: The isotopic representation of cesium is $_{55}^{137}\textrm{Cs}$

For c: The isotopic representation of strontium is $_{38}^{52}\textrm{Sr}$

Explanation:

The isotopic representation of an atom is: $_Z^A\textrm{X}$

where,

Z = Atomic number of the atom

A = Mass number of the atom

X = Symbol of the atom

For a:

We are given:

Number of neutrons = 78

Atomic number of iodine = 53 = Number of protons

Mass number = 53 + 78 = 131

Thus, the isotopic representation of iodine is $_{53}^{131}\textrm{I}$

For b:

We are given:

Number of neutrons = 82

Atomic number of cesium = 55 = Number of protons

Mass number = 55 + 82 = 137

Thus, the isotopic representation of cesium is $_{55}^{137}\textrm{Cs}$

For c:

We are given:

Number of neutrons = 52

Atomic number of strontium = 38 = Number of protons

Mass number = 38 + 52 = 90

Thus, the isotopic representation of strontium is $_{38}^{52}\textrm{Sr}$

3 0

3 years ago

What is the pH of .0003 M of NaOH

s344n2d4d5 [400]

We are given that the concentration of NaOH is 0.0003 M and are asked to calculate the pH

We know that NaOH dissociates by the following reaction:

NaOH → Na⁺ + OH⁻

Which means that one mole of NaOH produces one mole of OH⁻ ion, which is what we care about since the pH is affected only by the concentration of H⁺ and OH⁻ ions

Now that we know that one mole of NaOH produces one mole of OH⁻, 0.0003M NaOH will produce 0.0003M OH⁻

Concentration of OH⁻ (also written as [OH⁻]) = 3 * 10⁻⁴

pOH of the solution:

pOH = -log[OH⁻] = -log(3 * 10⁻⁴)

pOH = -0.477 + 4

pOH = 3.523

pH of the solution:

We know that the sum of pH and pOH of a solution is 14

pH + pOH = 14

pH + 3.523 = 14 [subtracting 3.523 from both sides]

pH = 10.477

8 0

3 years ago

Pharmacists sometimes measure medicines in the unit of "grains," where 1 gr = 65 mg. The label on a bottle of aspirin reads "Asp

viva [34]

Answer:

325mg of Aspririn

Explanation:

First you should note the information that the problem gives you:

- The bottle of Aspirin has 5gr (grains)

- 1gr(grain) = 65mg (miligrams)

Also, the problem is asking about how many aspirin are in 5 gr (grains), so you should use a conversion factor, as follows:

-First you should put the quantity you need to convert:

$5grAspirin$

-Then you write the denominator of the conversion factor that must have the same units that you want to convert, in this case gr:

$5grAspirin*\frac{}{1grAspirin}$

-Then you write the numerator with the units that you want to obtain and the numerical equivalence between the units, in this case:

$5grAspirin*\frac{65mgAspririn}{1grAspirin}$

-Finally you multiply numerators and divide by denominators:

$5grAspirin*\frac{65mgAspririn}{1grAspirin}=325mgAspririn$

8 0

3 years ago

To protect itself from herbivores, plants ______

9966 [12]

C.) both secrete toxins and have thorns (It simply depends on what kind of plant it is)

3 0

3 years ago

Read 2 more answers

Examine the reactants of the incomplete double-displacement reaction. 2NaCl + H2SO4 → __________. Which of the answer choices co

saw5 [17]

C because the sodium (cation) bonds with the sulphate (anion) and then chloride (anion) and hydrogen (acting as a cation) bond together

8 0

3 years ago