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2 years ago

Why are some resources, like fossils, found in some places and not in others?

Chemistry

1 answer:

devlian [24]2 years ago

6 0

Answer:

Because thats where the animal passed away

Explanation:

You might be interested in

How many hydrogen atoms are found in 3H2CO3?

Fiesta28 [93]

Answer:

Explanation:

The number of hydrogen atoms in the given compound is 6 atoms.

Given compound is:

3H₂CO₃

An atom is the smallest indivisible particles of an element.

In the compound;

3H₂CO₃

Elements Number of atoms

H 3(2) = 6

C 3(1) = 3

O 3(3) = 9

The number of hydrogen atoms in the compound is 6

5 0

2 years ago

I don't know how to do any of these.plz help.its a study guide for my chemistry exam tomorrow ✌

Vladimir [108]

6.02 x 1023 atoms weigh out 63.55 grams copper.

No. of Molecules in water = 3.5mole x (6.02 x 10^23) molecules/mole = 2.107 x 10^24 molecules of H2O

8 0

3 years ago

For the reaction of ammonia (NH3) with oxygen (O2) to produce water and nitric oxide (NO), how many moles of water are produced

asambeis [7]

Answer:

3.3 moles of H₂O.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

4NH₃ + 5O₂ —> 6H₂O + 4NO

From the balanced equation above,

4 moles of NH₃ reacted to produce 6 moles of H₂O.

Finally, we shall determine the number of mole of H₂O produced by the reaction of 2.2 moles of NH₃. This can be obtained as follow :

From the balanced equation above,

4 moles of NH₃ reacted to produce 6 moles of H₂O.

Therefore, 2.2 moles of NH₃ will react to produce = (2.2 × 6)/4 = 3.3 moles of H₂O.

Thus, 3.3 moles of H₂O were obtained from the reaction.

7 0

2 years ago

Thermal energy would naturally flow between objects at which temperatures?

marissa [1.9K]

Answer:

i think the answer is letter C. From 35°c to 45°c

Explanation:

sorry if it is wrong

4 0

2 years ago

A 5.00-mL sample of blood was treated with trichloroacetic acid to precipitate proteins. After centrifugation, the resulting sol

Anarel [89]

Explanation:

According to the Beer-lambert' s law,

Absrobance = absrobptitvity × lenght × concentration

So, if we will plot a graph between absrobance and concentration then we will obtain a straight line

Hence, formula to calculate slope of the graph is as follows.

The slope of graph = $\frac{\text{difference in absrobance at two points}}{\text{difference in concentrations at those points}}$

The given data is as follows.

$A_{1}$ = 0.412 (first point)

$A_{2}$ = 0.642 (second point)

$C_{1}$ = 0.240 ppm (first point)

$C_{2}$ = 0.475 ppm (second point)

Hence, putting these values into the above formula we will calculate the value of slope as follows.

Slope = $\frac{\text{difference in absrobance at two points}}{\text{difference in concentrations at those points}}$

= $\frac{0.642 - 0.412}{0.475 - 0.240}$

= $\frac{0.23}{0.235}$

= 0.978

It is known that for the graph, line equation can be written as follows.

y = mx + c ........... (1)

where, C = intercept

m = slope

Hence, calculate the value of intercept as follows.

0.412 = $0.24 \times 0.978$ + c

c = 0.178

As it is given that the absorbance values 0.454 (the y-axis value). Therefore, putting this value into equation (1) we get the following.

y = mx + c

0.454 = $x \times 0.978$ + 0.178

0.276 = 0.978x

x = 0.282 ppm

Thus, we can conclude that the concentration of Pb in the given sample is 0.282 ppm.

3 0

3 years ago