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3 years ago

How do you identify unknown chemicals.

Chemistry

1 answer:

QveST [7]3 years ago

7 0

Answer:

Preventing Unknown Chemicals

Label all chemical containers, including beakers, flasks, vials, and test tubes.

Immediately replace labels that have fallen off or that are deteriorated.

Label containers using chemical names. ...

Archived research samples are often stored in boxes containing hundreds of small vials.

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Be sure to answer all parts. The percent by mass of bicarbonate (HCO3−) in a certain Alka-Seltzer product is 32.5 percent. Calcu

pochemuha

Answer : The volume of $CO_2$ will be, 514.11 ml

Explanation :

The balanced chemical reaction will be,

$HCO_3^-+HCl\rightarrow Cl^-+H_2O+CO_2$

First we have to calculate the mass of $HCO_3^-$ in tablet.

$\text{Mass of }HCO_3^-\text{ in tablet}=32.5\% \times 3.79g=\frac{32.5}{100}\times 3.79g=1.23175g$

Now we have to calculate the moles of $HCO_3^-$ .

Molar mass of $HCO_3^-$ = 1 + 12 + 3(16) = 61 g/mole

$\text{Moles of }HCO_3^-=\frac{\text{Mass of }HCO_3^-}{\text{Molar mass of }HCO_3^-}=\frac{1.23175g}{61g/mole}=0.0202moles$

Now we have to calculate the moles of $CO_2$ .

From the balanced chemical reaction, we conclude that

As, 1 mole of $HCO_3^-$ react to give 1 mole of $CO_2$

So, 0.0202 mole of $HCO_3^-$ react to give 0.0202 mole of $CO_2$

The moles of $CO_2$ = 0.0202 mole

Now we have to calculate the volume of $CO_2$ by using ideal gas equation.

$PV=nRT$

where,

P = pressure of gas = 1.00 atm

V = volume of gas = ?

T = temperature of gas = $37^oC=273+37=310K$

n = number of moles of gas = 0.0202 mole

R = gas constant = 0.0821 L.atm/mole.K

Now put all the given values in the ideal gas equation, we get :

$(1.00atm)\times V=0.0202 mole\times (0.0821L.atm/mole.K)\times (310K)$

$V=0.51411L=514.11ml$

Therefore, the volume of $CO_2$ will be, 514.11 ml

6 0

3 years ago

How is a waveform shown on the oscilloscope different from a compressional wave?

kiruha [24]

<span>The waveform shown on an oscilloscope is a signal graph of voltage as a function of time.

Such a signal isn't considered by the oscilloscope to be traveling, and hence the oscilloscope itself doesn't see the signal as a wave.

In the wire though, it "sort of" is a longitudinal wave of electrons...but then again, there is more to the story. There is also a radio EM wave in the surrounding electric and magnetic fields, and the engineers interested in long distance signal transmission study these fields to estimate velocity factor. </span>

3 0

4 years ago

Read 2 more answers

Which of the following is the correct molecular shape of NH3?

AnnZ [28]

A bent

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5 0

3 years ago

What element has 1 proton, 1 neutron, and 2 electrons?

Olegator [25]

Answer:

Tritium

Tritium is a hydrogen isotope consisting of one proton, two neutrons and one electron. It is radioactive, with a half-life of 12.32 years.

Explanation:

hope it helps :)))

6 0

3 years ago

A gas has a density of 0.902 g l at stp what is the molar mass of this gas

S_A_V [24]

According to the molar gas volume, one mole of a gas occupies a volume of 22400 cm³ or 22.4 liters. The standard temperatures and pressures conditions are temperature of 0 degrees Celsius or 273 kelvin and an absolute pressure of 103.325 kPa or 1 atm. In this case, the density is 0.902 g/l and the volume is 22400 cm³,
therefore, the molar mass will be;
0.902 g/ L ×22.4 liters = 20.2048g

8 0

3 years ago