5. How many significant figures are in the measurement +0.500 mg?

Which pair of elements is MOST likely to chemically combine and form ionic bonds?

Hoochie [10]

The answer is letter c

3 0

3 years ago

How much gold is harvested per ton of earth from the underground mine?

Karolina [17]

<span> 0.005 parts per million</span>

4 0

3 years ago

Read 2 more answers

Chromium has an atomic mass of 51.9961 u and consists of four isotopes, 50 Cr , 52 Cr , 53 Cr , and 54 Cr . The 52 Cr isotope ha

Troyanec [42]

Answer : The atomic mass of $_{24}^{53}\textrm{Cr}$ isotope is 52.8367 amu

Explanation :

We know that:

Total percentage abundance of the isotope = 100 %

Percentage abundance of $_{24}^{50}\text{Cr}\text{ and }_{24}^{53}\textrm{Cr}\text{ isotopes}=[100-(83.79+2.37)]=13.84\%$

We are given:

Ratio of $_{24}^{50}\textrm{Cr}\text{ and }_{24}^{53}\textrm{Cr}$ isotopes = 0.4579 : 1

Percentage abundance of $_{24}^{50}\textrm{Cr}$ isotope = $\frac{0.4579}{(0.4579+1)}\times 13.84\%=4.37\%$

Percentage abundance of $_{24}^{53}\textrm{Cr}$ isotope = $\frac{1}{(0.4579+1)}\times 13.84\%=9.49\%$

Average atomic mass of an element is defined as the sum of masses of each isotope each multiplied by their natural fractional abundance.

Formula used to calculate average atomic mass follows: $\text{Average atomic mass }=\sum_{i=1}^n\text{(Atomic mass of an isotopes)}_i\times \text{(Fractional abundance})_i$ .....(1)

Let the mass of $_{24}^{53}\textrm{Cr}$ isotope be 'x'

For $_{24}^{50}\textrm{Cr}$ isotope:

Mass of $_{24}^{50}\textrm{Cr}$ isotope = 49.9460 amu

Percentage abundance of $_{24}^{50}\textrm{Cr}$ = 4.37 %

Fractional abundance of $_{24}^{50}\textrm{Cr}$ isotope = 0.0437

For $_{24}^{52}\textrm{Cr}$ isotope:

Mass of $_{24}^{52}\textrm{Cr}$ isotope = 51.9405 amu

Percentage abundance of $_{24}^{52}\textrm{Cr}$ isotope = 83.79 %

Fractional abundance of $_{24}^{52}\textrm{Cr}$ isotope = 0.8379

or $_{24}^{53}\textrm{Cr}$ isotope:

Mass of $_{24}^{53}\textrm{Cr}$ isotope = x amu

Percentage abundance of $_{24}^{53}\textrm{Cr}$ isotope = 9.49 %

Fractional abundance of $_{24}^{53}\textrm{Cr}$ isotope = 0.0949

For $_{24}^{54}\textrm{Cr}$ isotope:

Mass of $_{24}^{54}\textrm{Cr}$ isotope = 53.9389 amu

Percentage abundance of $_{24}^{54}\textrm{Cr}$ isotope = 2.37 %

Fractional abundance of $_{24}^{54}\textrm{Cr}$ isotope = 0.0237

Average atomic mass of chromium = 51.9961 amu

Putting values in equation 1, we get:

$51.9961=[(49.9460\times 0.0437)+(51.9405\times 0.8379)+(x\times 0.0949)+(53.9389\times 0.0237)]\\\\x=52.8367amu$

Hence, the atomic mass of $_{24}^{53}\textrm{Cr}$ isotope is 52.8367 amu

4 0

4 years ago

What is the molarity of a solution that has a volume of 5.90 L and contains 0.21 moles of calcium chloride?

allsm [11]

Answer:

.036 M

Explanation:

Molarity = number of moles/volume.

Molarity = .21/5.90 = .036

- Hope this helps! If youstill do not understand or need a more in-depth explanation please let me know.

4 0

3 years ago

The two covalent bonds in a water molecule are polar because

elena55 [62]

Answer:

The correct option is the A

Explanation:

Like oxygen is more electronegative than hydrogen, it attracts electrons stronger than hydrogen. Therefore the two covalent bonds are polar.

The option b is incorrect because if oxygen and hydrogen had similar electronegativities, they would form no-polar bonds.

The option c is incorrect because oxygen is more electronegative than hydrogen (you can check that in a periodic table).

The options d and e are incorrect because the molecular size or hydrophilic don't influence the type bond.

3 0

3 years ago