10. A(n) eclipse occurs at a full moon when Earth is directly between the moon and the sun.

In the lab you weigh out 76.02 g of Iron (Fe). How many moles of Iron do you have in the sample. (Your answer must have a unit..

son4ous [18]

Answer:

We have 1.361 moles in the sample

Explanation:

Mass of iron = 76.02g

Molar mass of iron = 55.845 g/ mole ( This we can find in the periodic table, and menas that 1 mole of iron has a mass of 55.845 g).

To calculate the number of moles we will use following formula:

moles (n) = mass / molar mass

moles iron = 76.02g / 55.845 g/ mole

moles iron = 1.36127 moles

To use the correct number of significant digits we use the following rule for multiplication and division :

⇒ the number with the least number of significant figures decides the number of significant digits.

⇒76.02 has 4 digits ( 2 after the comma) and 55.845 has 5 digits (3 after the comma).

⇒ this means 1.361 moles

We have 1.361 moles in the sample

3 0

3 years ago

An FAS calibration curve (absorbance, y-axis vs. FAS in g/mL) gave an equation he regression line of: y-3678(x)+0.056. If an unk

mezya [45]

Answer:

FAS concentration = 1.61*10^-4M

Explanation:

Beer Lambert's law relates the absorbance (A) of a substance to its concentration (c) as:

$A = \epsilon lc----(1)$

where ε = molar absorption coefficient

l = path length

A plot of 'A' vs 'c' gives a straight line with slope = εl

In addition absorbance (A) is related to % Transmittance (%T) as:

A = 2-log%T----(2)

For the FAS solution, the corresponding calibration fit is given as:

y = 3678(x) + 0.056

This implies that the slope = εl = 3678

It is given that %T = 25.6%

$A = 2-log(25.6)=0.592$

Based on equation(1):

$c = \frac{A}{\epsilon l}=\frac{0.592}{3678}=1.61*10^{-4}M$

8 0

2 years ago

Uranium-236 is _____. created by fusion reactions an unstable isotope of uranium created from four hydrogen atoms used in the H-

nata0808 [166]

<span>Uranium-236 is intermediate nuclei. created by fusion reactions an unstable isotope of uranium created from four hydrogen atoms used in the H-bomb.

Following is the reaction involved in above process:

</span> $^{235}U$ + $^{1}n$ → $^{236}U$ → $^{144}Ba$ + $^{89}Kr$ + 3 $^{1}n$ <span> + 177 MeV
</span>
Here,
$^{235}U$ = Fission material,
$^{1}n$ = projectile,
$^{236}U$ = intermediate nuclei,
$^{144}Ba$ and $^{89}Kr$ = Fission product

8 0

2 years ago

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Question 4 to make a 0.500 m solution, one could take 0.500 moles of solute and add 1.00 l of solvent. enough solvent to make 1.

stealth61 [152]

The answer is enough solvent to make 1.00 L of solution. Since molarity is the number of moles of solute in one liter of solution, adding 0.500 mole solute to one liter solvent might not result to a solution with one liter total volume. Less than one liter solvent is first added to dissolve 0.500 mole solute and then the solution is carefully filled with more solvent until the solution reaches to one liter total volume. Hence, the resulting solution is a 0.500M concentration.

7 0

3 years ago

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Help help help I will give brainliest

vampirchik [111]

Answer:

its b alkyne

Explanation:

brinliest po plsss

8 0

2 years ago

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10. A(n) eclipse occurs at a full moon when Earth is directly between the moon and the sun.​

10. A(n) eclipse occurs at a full moon when Earth is directly between the moon and the sun.