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3 years ago

How do scientists use the Doppler affect to understand the universe?

1 answer:

8 0

Astronomers use the Doppler effect<span> to measure the frequency of light waves as an object is moving with respect to the observer</span>

You might be interested in

How many moles is 17.6 g NaOH?

Lynna [10]

Answer:

$\boxed {\boxed {\sf D. 0.440 \ mol \ NaOH}}$

Explanation:

To convert from moles to grams, the molar mass is used (mass of 1 mole). The values are the same as the atomic masses on the Periodic Table, but the units are grams per mole (g/mol) instead of atomic mass units.

<h3>1. Molar Mass</h3>

We are given the compound sodium hydroxide (NaOH) and we need to look up the molar masses of the individual elements.

Na: 22.9897693 g/mol
O: 15.999 g/mol
H: 1.008 g/mol

The formula for the compound has no subscripts, so there is 1 mole of each element in 1 mole of the substance. We can simply add the molar masses.

NaOH: 22.9897693 + 15.999 + 1.008 = 39.9967693 g/mol

This means there are 39.9967693 grams of sodium hydroxide in 1 mole.

<h3>2. Convert Grams to Moles </h3>

Use the molar mass we found as a ratio.

$\frac {39.9967693 \ g \ NaOH}{ 1 \ mol \ NaOH}$

Since we are converting 17.6 grams of NaOH to moles, we multiply by this value.

$17.6 \ g\ NaOH *\frac {39.9967693 \ g \ NaOH}{ 1 \ mol \ NaOH}$

Flip the ratio so the units of grams of NaOH cancel.

$17.6 \ g\ NaOH *\frac {1 \ mol \ NaOH}{ 39.9967693 \ g \ NaOH}$

$17.6 *\frac {1 \ mol \ NaOH}{ 39.9967693}$

$\frac{17.6 }{ 39.9967693} \ mol \ NaOH$

$0.4400355406 \ mol \ NaOH$

<h3>3. Round </h3>

The original measurement of grams has 3 significant figures, so our answer must have the same. For the number we calculated, that is the thousandth place.

0.4400355406

The 0 in the ten thousandths place (in bold above) tells us to leave the 0 in the thousandth place.

$0.440 \ mol \ NaOH$

17.6 grams of sodium hydroxide are equal to <u>0.440 moles of sodium hydroxide.</u>

3 0

2 years ago

Consider the following reaction:

Kitty [74]

Answer : The value of equilibrium constant (Kc) is, 0.0154

Explanation :

The given chemical reaction is:

$SO_2Cl_2(g)\rightarrow SO_2(g)+Cl_2(g)$

Initial conc. $2.4\times 10^{-2}$ 0 0

At eqm. $(2.4\times 10^{-2}-x)$ x x

As we are given:

Concentration of $Cl_2$ at equilibrium = $1.3\times 10^{-2}M$

That means,

$x=1.3\times 10^{-2}M$

The expression for equilibrium constant is:

$K_c=\frac{[SO_2][Cl_2]}{[SO_2Cl_2]}$

Now put all the given values in this expression, we get:

$K_c=\frac{(x)\times (x)}{2.4\times 10^{-2}-x}$

$K_c=\frac{(1.3\times 10^{-2})\times (1.3\times 10^{-2})}{2.4\times 10^{-2}-1.3\times 10^{-2}}$

$K_c=0.0154$

Thus, the value of equilibrium constant (Kc) is, 0.0154

4 0

2 years ago

a european cheese making recipe calls for 2.50 kg of whole milk. An american wishes to make the recipe has only measuring cups,

Firlakuza [10]

To determine the number of cups of milk, we first calculate for the volume of the milk needed. Then, we use a conversion factor for the volume from cubic centimeter to cups. From literature, 1 cubic centimeter is equal to 0.0042 cup. We do as follows:

Volume of milk = ( 2.50 kg ) ( 1000 g / 1 kg ) / 1.03 g /cm^3 = 2427.18 cm^3
cups of milk = 2427.18 cm^3 ( 0.0042 cup / 1 cm^3 ) = 10.19 cups

5 0

2 years ago

2. What is an example of a molecule<br> with different types of atoms?

agasfer [191]

Answer:

a compound

Explanation:

A molecule with multiple atoms is compound like water it's made up of 1 oxygen and two hydrogen.

4 0

2 years ago

Which of the following explains the process of radiation?

den301095 [7]

Answer:

When heat gets transferred through electromagnetic waves that move through space .

Explanation:

Radiation is the propagation of energy in the form of electromagnetic waves or subatomic particles through a vacuum or a material medium.

8 0

2 years ago