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2 years ago

Why can air pollution be a problem even if you do not live next to a factory?

Chemistry

1 answer:

Lilit [14]2 years ago

6 0

Answer:

cause pollution on a small scale can make big difference......

Explanation:

factory isn't a single source of pollution

there are many more.....

You might be interested in

I NEED HELP FAST!!!!! Can you tell me about the development of the periodic table??? I have a DBA in a few minutes and I don't k

weqwewe [10]

Dimitri Mendeleev was the first to put elements together on a table. He knew there were elements missing but he noticed a trend in some of the elements known at the time. Sodium, Lithium and other alkali metals all have the same properties so he put them under the same column and created other columns with similar attributes (Halogens, Noble gases, Alkaline earth metals). Over the years, new elements were discovered and put into the rough outline that Mendeleev created.

I hope that is about what you wanted.

5 0

3 years ago

Hi ! Could someone help me out with this last part to my chemistry practice ? Thank you !

skelet666 [1.2K]

After 100years, sample is 250g

After 200 years, sample is 125g

After 300years, sample is 62.5 g

7 0

3 years ago

Should we only write condensed formula in chemical equations (for lessons like carbon and compounds). What did your teachers say

Firlakuza [10]

Answer:

Here's what I get.

Explanation:

If your teachers don't ask for a specific type of formula, a condensed structural formula should be OK.
If they ask specifically for a structural formula or a bond-line formula, that is what you must give.

Bottom line: ask your teachers in advance what they expect.

7 0

3 years ago

How many moles is 2.55 x 10 to the power of 26 atoms of Neon?

Yakvenalex [24]

Answer:

424 mol

Explanation:

Step 1: Given data

Number of atoms of Neon: 2.55 × 10²⁶ atoms

Step 2: Calculate the number of moles corresponding to 2.55 × 10²⁶ atoms of Neon

In order to convert atoms into moles, we need a conversion factor, which is Avogadro's number: there are 6.02 × 10²³ atoms of Neon in 1 mole of atoms of Neon.

2.55 × 10²⁶ atoms × (1 mol/6.02 × 10²³ atoms) = 424 mol

4 0

3 years ago

How many moles of sodium carbonate are contained by 57.3g of sodium carbonate

Lady_Fox [76]

Answer:

$\boxed {\boxed {\sf 0.541 \ mol \ Na_2CO_3}}$

Explanation:

We are asked to find how many moles of sodium carbonate are in 57.3 grams of the substance.

Carbonate is CO₃ and has an oxidation number of -2. Sodium is Na and has an oxidation number of +1. There must be 2 moles of sodium so the charge of the sodium balances the charge of the carbonate. The formula is Na₂CO₃.

We will convert grams to moles using the molar mass or the mass of 1 mole of a substance. They are found on the Periodic Table as the atomic masses, but the units are grams per mole instead of atomic mass units. Look up the molar masses of the individual elements.

Na: 22.9897693 g/mol
C: 12.011 g/mol
O: 15.999 g/mol

Remember the formula contains subscripts. There are multiple moles of some elements in 1 mole of the compound. We multiply the element's molar mass by the subscript after it, then add everything together.

Na₂ = 22.9897693 * 2= 45.9795386 g/mol
O₃ = 15.999 * 3= 47.997 g/mol
Na₂CO₃= 45.9795386 + 12.011 + 47.997 =105.9875386 g/mol

We will convert using dimensional analysis. Set up a ratio using the molar mass.

$\frac {105.9875386 \ g \ Na_2CO_3}{1 \ mol \ Na_2CO_3}$

We are converting 57.3 grams to moles, so we multiply by this value.

$57.3 \ g \ Na_2CO_3} *\frac {105.9875386 \ g \ Na_2CO_3}{1 \ mol \ Na_2CO_3}$

Flip the ratio so the units of grams of sodium carbonate cancel.

$57.3 \ g \ Na_2CO_3} *\frac {1 \ mol \ Na_2CO_3}{105.9875386 \ g \ Na_2CO_3}$

$57.3 } *\frac {1 \ mol \ Na_2CO_3}{105.9875386 }$

$\frac {57.3 }{105.9875386 } \ mol \ Na_2CO_3$

$0.5406295944 \ mol \ Na_2CO_3$

The original measurement of moles has 3 significant figures, so our answer must have the same. For the number we found that is the thousandth place. The 6 in the ten-thousandth place to the right tells us to round the 0 up to a 1.

$0.541 \ mol \ Na_2CO_3$

There are approximately <u>0.541 moles of sodium carbonate</u> in 57.3 grams.

6 0

2 years ago