Ask question

Ask question

All categories

sleet_krkn [62]

2 years ago

5

What is flame over circle mean?

2 answers:

Tom [10]2 years ago

7 0

Flame over Circle. This symbol on a chemical label means that the substance is an oxidizer. Oxidizers may cause a fire by increasing the concentration of oxygen in the air.

Dominik [7]2 years ago

5 0

That means flammable

You might be interested in

If I add the same amounts of ice to water, cooking oil, and corn syrup then they will lose heat at the same/different rates beca

Vilka [71]

Ice is cold and water cools down heat, cooking oil isn’t hot unless you add it to heat, corn syrup isn’t hot unless you add it to heat as well so, they’d all lose heat at the same/different rates because they are all cooled beverages/subjects.

5 0

2 years ago

How many grams of carbon (C) would be present in carbon monoxide (CO) that contains 2.666 grams of oxygen (O)? For example if th

oee [108]

Given :

Mass of oxygen containing carbon monoxide (CO) is 2.666 gram .

To Find :

How many grams of carbon (C) would be present in carbon monoxide (CO) that contains 2.666 grams of oxygen (O) .

Solution :

By law of constant composition , a given chemical compound always contains its component elements in fixed ratio (by mass) and does not depend on its source and method of preparation.

So , volume of solution does not matter .

Moles of oxygen , $n=\dfrac{2.666}{16}=0.167\ mole$ .

Now , molecule of CO contains 1 mole of C .

So , moles of C is also 0.167 mole .

Mass of carbon , $m=12\times 0.167=2\ g$ .

Therefore , mass of carbon is 2 grams .

Hence , this is the required solution .

5 0

2 years ago

How many moles of H2O are needed to produce 5.6 mol of NaOH?<br> Na2O + H2O --> 2NaOH

navik [9.2K]

Answer: 2.8 moles

Explanation:

The balanced equation below shows that 1 mole of sodium oxide reacts with 1 mole of water to form 2 moles of sodium hydroxide respectively.

Na2O + H2O --> 2NaOH

1 mole of H2O = 2 moles of NaOH

Let Z moles of H2O = 5.6 mole of NaOH

To get the value of Z, cross multiply

5.6 moles x 1 mole= Z x 2 moles

5.6 = 2Z

Divide both sides by 2

5.6/2 = 2Z/2

2.8 = Z

Thus, 2.8moles of H2O are needed to produce 5.6 mol of NaOH

3 0

2 years ago

When copper metal is added to nitric acid, the following reaction takes place

zlopas [31]

Answer:

The volume of NO₂ gas collected over water at 25.0 °C is 1.68 Liters.

Explanation:

$Cu (s) + 4 HNO_3 (aq) \rightarrow Cu(NO_3)_2 (aq) + 2 H_2O (l) + 2 NO_2 (g)$

Moles of copper = $\frac{2.01 g}{63.55 g/mol}=0.03163 mol$

According to reaction, 1 mol of copper gives 2 moles of nitrogen dioxide gas.

Then 0.03613 moles of copper will give:

$\frac{2}{1}\times 0.03163 mol=0.06326 mol$ of nitrogen dioxide gas

Moles of nitrogen dioxide gas = n = 0.06326 mol

Pressure of the gas = P

P = Total pressure - vapor pressure of water

P = 726 mmHg - 23.8 mmHg = 702.2 mmHg

P = 0.924 atm (1 atm = 760 mmHg)

Temperature of the gas = T = 25.0°C =298.15 K

Volume of the gas = V

$PV=nRT$

$V=\frac{0.06326 mol\times 0.0821 atm L/mol K\times 298.15 K}{0.924 atm}$

V = 1.68 L

The volume of NO₂ gas collected over water at 25.0 °C is 1.68 Liters.

3 0

2 years ago

Why is refraction so important in eyeglasses.

miss Akunina [59]

It helps our eyes to see better. For example: If you can't read a book because you see that is blurry, you might need glasses to see it much clearer

7 0

2 years ago