Two Chemistry questions 30 points

224/88Ra+4/2He+? find the missing isotope

andre [41]

Do u have a picture if so post it please

8 0

3 years ago

A gas occupies 200ml at a temperature of 26 degrees Celsius and 76mmHg pressure. Find the volume at -3degree Celsius with the pr

sergey [27]

Answer:

184.62 ml

Explanation:

Let $p_1, v_1,$ and $T_1$ be the initial and $p_2, v_2,$ and $T_2$ be the final pressure, volume, and temperature of the gas respectively.

Given that the pressure remains constant, so

$p_1=p_2$ ...(i)

$v_1$ = 200 ml

$T_1= 26 ^{\circ}C = 273+26 =299$ K

$T_2= 3 ^{\circ}C = 273+3 =276$ K

From the ideal gas equation, pv=mRT

Where p is the pressure, v is the volume, T is the temperature in Kelvin, m is the mass of air in kg, R is the specific gas constant.

For the initial condition,

$p_1v_1=mRT_1 \\\\mR= \frac{p_1v_1}{T_1}\cdots(ii)$

For the final condition,

$p_2v_2=mRT_2 \\\\mR= \frac{p_2v_2}{T_2}\cdots(iii)$

Equating equation (i), and (ii)

$\frac{p_1v_1}{T_1}=\frac{p_2v_2}{T_2}$

$\frac{v_1}{T_1}=\frac{v_2}{T_2}$ [from equation (i)]

$v_2=\frac{T_2}{T_1} \times v_1$

Putting all the given values, we have

$v_2=\frac{276}{299} \times 200 = 184.62 \; ml$

Hence, the volume of the gas at 3 degrees Celsius is 184.62 ml.

7 0

3 years ago

Every atom's goal is to get ________ electrons in its valence shell.

sdas [7]

Every atom tends to form configuration of noble gas , with the 8 electrons in valence shell.

6 0

3 years ago

Match each statement with a layer of the atmosphere. There will be two statements for each layer.

LuckyWell [14K]

The troposphere:

H. This layer can have thunderstorms or clear, sunny skies.

A. The biosphere interacts most with this layer.

The stratosphere:

B. It is the second layer from Earth's surface.

G. Winds are strong and steady in this layer.

The mesosphere:

E. It is heated by the ozone layer beneath it.

D. This layer is where most meteor showers occur.

The thermosphere :

F. It contains the ionosphere and exosphere.

C. It contains layers of single, unmixed gas.

Explanation:

Depending on the Earth's temperature the atmosphere can be separated into layers. The troposphere, the stratosphere, the mesosphere and the thermosphere are those layers. The lowest layer is named as Troposphere (0-10 km from the Earth outer surface), it comprises about 75% of the atmosphere's total air and nearly most the water vapor.

Stratosphere (10-30) includes much of the surface ozone. The change in height temperature arises as this ozone absorbs ultraviolet (UV) radiation from the sun. The temperature in Mesosphere (30-50 Km) declines again with height, hitting a minimum of about -90 ° C at the "mesopause." Above this thermosphere (50-400 Km) is settled which is a area where temperatures rise with height once again. The penetration of intense UV and X-ray radiation from the sun induces this temperature rise.

6 0

3 years ago

Predict the effect of adding a non competitive inhibitor to the reaction mixture on the rate of reaction at a high substrate con

Darya [45]

Answer:

A noncompetitive inhibitor can only bind to an enzyme with or without a substrate at several places at a particular point in time

Explanation:

this is because It changes the conformation of an enzyme as well as its active site, which makes the substrate unable to bind to the enzyme effectively so that the efficiency of the enzyme decreases. A noncompetitive inhibitor binds to the enzyme away from the active site, altering/distorting the shape of the enzyme so that even if the substrate can bind, the active site functions less effectively and most of the time also the inhibitor is reversible

8 0

3 years ago