All categories

3 years ago

PLEASE HELP ME!!!!!!!!!!!!

Chemistry

1 answer:

zhuklara [117]3 years ago

8 0

Answer:

idk what this is

Explanation:

You might be interested in

Determine the number of centiliters in 2.4 x 10^3 milliliters.

AnnZ [28]

2.4(10^3)

=2.4*10^3

=2.4*(10*10*10)

=2400 milliliters

To centiliters is 2400mL= 240.0000cl. 

8 0

3 years ago

A 250 mL sample of gas is collected over water at 35°C and at a total pressure of 735 mm Hg. If the vapor pressure of water at 3

ELEN [110]

Answer:

The volume of the gas sample at standard pressure is 819.5ml

Explanation:

Solution Given:

let volume be V and temperature be T and pressure be P.

$V_1=250ml$

$V_2=?$

$P_{total}=735 mmhg$

1 torr= 1 mmhg

42.2 torr=42.2 mmhg

so,

$P_{water}=42.2mmhg$

$T_1=35°C=35+273=308 K$

Now

firstly we need to find the pressure due to gas along by subtracting the vapor pressure of water.

$P_{gas}=P_{total}-P_{water}$

=735-42.2=692.8 mmhg

Now

By using combined gas law equation:

$\frac{P_1*V_1}{T_1} =\frac{P_2*V_2}{T_2}$

$V_2=\frac{P_1*}{P_2}*\frac{T_2}{T_1} *V_1$

$V_2=\frac{P_gas}{P_2}*\frac{T_2}{T_1} *V_1$

Here $P_2 \:and\: T_2$ are standard pressure and temperature respectively.

we have

$P_2=750mmhg \:and\: T_2=273K$

Substituting value, we get

$V_2=\frac{692.8}{750}*\frac{273}{308} *250$

$V_2= 819.51 ml$

4 0

2 years ago

Which reaction removes hydrogen ions from the blood?

Mrrafil [7]

Pulmonary ventilation, and carbonic acid-bicarbonate buffering system

3 0

3 years ago

A sample of hydrogen was collected by water displacement at 23.0°C and an atmospheric pressure of 735 mmHg. Its volume is 568 mL

ziro4ka [17]

Answer:

V = 552 mL or 0.552 L

Explanation:

First, we need to calculate the number of moles of H2 using the ideal gas equation which is:

PV = nRT

Solving for n:

n = PV / RT

Where:

P = Pressure

V = Volume

R = Gas constant (0.082 L atm / K mol)

T = Temperature in K

Let's convert first both pressure in atm, remember that 1 atm = 760 mmHg

P = 735 / 760 = 0.967 atm

Pwater = 21 / 760 = 0.028 atm

Finally temperature to Kelvin:

T = 23 + 273.15 = 296.15 K

Now, at first the hydrogen was collected by water displacement so pressure is:

P = 0.967 - 0.028 = 0.939 atm

Now the moles of hydrogen:

n = 0.939 * 0.568 / 0.082 * 296.15

n = 0.022 moles

Now that we have the moles, let's calculate the volume when the pressure is 735 mmHg

V = nRT/P

V = 0.022 * 0.082 * 296.15 / 0.967

V = 0.552 L or 552 mL

This is the volume that hydrogen occupies.

6 0

3 years ago

Tooth enamel is ca5(po4)3(oh). calculate the percent composition of the elements present.

Mama L [17]

We shall find the molar mass first.
Ca5(PO4)3(OH) = (40 * 5) + 3 (31 + 4(16)) + 16 + 1 = 200 + 285 + 17 = 485 + 17 = 502.
Percent of Calcium = 200/ 502 * 100 = 39.8%
Percent of Phosphorus = 91/502 * 100 = 18.1%
Percent of Hydrogen = 1/502 * 100 = 0.19%
Percent of Oxygen = 100 - (39.8 + 18.1 + 0.19) = 41.91%

8 0

3 years ago

Read 2 more answers