Two questions on pressure and solubility

1。Using the volume 4 5 10 -5 = 0,8 10 5 5 at the mass of the composite material, the total mass 45 + 5 = 50 is calculated and the force is 500n, and then the pressure at the composite material is 10 -32 volume density to obtain the alcohol mass 500 95% 0,8 = 38 grams.

Calculate the amount of solute required 1000 75%=750 From the previous question, we can see that there are 38 grams per 500 ml with 750 38=? I'm sorry, I didn't bring pen and paper, that's all I have to say.

This asked the 3rd floor to calculate the 3rd floor, please correct the typo the next time you paste it.

And then you multiply the total volume by the density to get the mass, and then subtract the mass from the mass and the mass is the mass of the water that should be added.

1. When studying the law of the internal pressure of the liquid, Xiaoliang used two liquids A and B to conduct many experiments, and drew an image of the change of liquid pressure with depth according to the experimental data, as shown in the figure on the right, then the density relationship between the two liquids of A and B is ( ) a, b, c, d, the condition is insufficient, and it cannot be determined 2. As shown in the figure, the outline of the sole part of the shoe drawn by a junior high school student weighing 672n when standing on graph paper, the area of each square is, then when the student's feet stand on the horizontal ground, The more accurate pressure value on the ground is ( ) a, b, c, d, 3, (multiple choice) Summer is coming, Wei Wei put ice cubes in the cup with cold boiled water to make a cold drink, when the ice cubes melt, what does not change is ( ) a, the height of the water surface in the cup b, the pressure of the cup on the table c, the pressure of water on the bottom of the cup d, the pressure of water on the bottom of the cup.

2.The following statements about stress that you think are incorrect; (a.The direction of pressure is always perpendicular to the compression surface. b.Pressure is gravity.

c.The pressure is sometimes equal to the gravitational force of the object, and sometimes it is less than the gravitational force of the object.

d.Pressure is sometimes independent of gravity, such as when you press a thumbtack with your hand.

3.When a test tube containing liquid is placed vertically at an angle, the pressure of the liquid on the bottom of the test tube will be; (

a.Grow bigger bSmaller cNo change DCan't be sure.

4.The laws of fluid pressure and velocity are applied to make the object move upward: (a balloon lift-off, b submarine floating, c large passenger plane lift-off, d rocket lift-off.

The higher the pressure, the greater the solubility of gases, for example, carbon dioxide in carbonated beverages is dissolved into the water by pressurization. For example, when the soda bottle is opened, the pressure in the bottle decreases, and a large number of bubbles can be seen.

At a certain temperature and pressure, the highest amount of gas dissolved in a certain amount of solvent is called the solubility of the gas. It is usually expressed as the maximum volume dissolved in 1 volume of solvent at a constant temperature. For example, if hydrogen can be dissolved in 100ml of water at 20 hours, it is expressed as water, etc.

The solubility of gas is not only related to the nature of gas and solvent properties, but also related to temperature and pressure, and its solubility generally decreases with the increase of temperature. Regarding the solubility of gases dissolved in liquids, in 1803 the British chemist WHenry, based on the study of dilute solutions, summed up a law called Henry's Law.

The higher the pressure, the greater the solubility of the gas, for example, the carbon dioxide in the carbonated drinks we drink is dissolved into the water by pressurization.

The lower the pressure, the lower the solubility of the gas, for example, when the soda bottle is opened, the pressure in the bottle decreases, and a large number of bubbles can be seen.

The higher the temperature, the lower the solubility of the gas, for example, when boiling water, you can see a lot of small bubbles, which are the escape of the gas dissolved in the water by heating.

The lower the temperature, the greater the solubility of the gas, for example, in winter the oxygen content of the lake water is higher than in the summer.

When the total pressure of the type II system increases, the solubility of the solute must increase (grinding orange).

a.That's right. b.Mistake.

Correct Answer: False.

The solubility of a gas is first determined by the properties of the gas, and also varies with the pressure of the gas and the temperature of the solvent. For example, at 20, the pressure of the gas is 101

kpa, the volume of dissolved gas in 1L of water is: ammonia is 702

l, hydrogen is.

l, oxygen is.

l。Ammonia is easily soluble in water because ammonia is a polar molecule, and water is also a polar molecule, and ammonia molecules and water molecules can also form hydrogen bonds, and significant hydration occurs, so its solubility is very large; Hydrogen and oxygen are non-polar molecules, so their solubility in water is very small.

When the pressure is constant, the solubility of the gas decreases as the temperature increases. This is no exception for gases, because when the temperature rises, the rate of movement of gas molecules increases, and it is easy to escape from the surface of the water.

When the temperature is constant, the solubility of the gas increases with the increase of the pressure of the gas. This is because when the pressure increases, the concentration of the gas on the liquid surface increases, therefore, more gas molecules enter the liquid surface than those that escape from the liquid surface, resulting in a greater solubility of the gas. In addition, the solubility of the gas is proportional to the pressure (partial pressure) of the gas within a certain range (provided that the gas does not chemically change with water).

For example, at 20, the pressure of hydrogen is 101

kpa, hydrogen at 1

The solubility in the water is.

l；Also in 20, in 2 101

kpa, hydrogen at 1

The solubility in the water is.

l×2＝l。

Solid solubility has little to do with air pressure.

The solubility of the gas increases as the pressure increases.

When the temperature is constant, the solubility of the gas increases with the increase of the pressure of the gas. This is because when the pressure increases, the concentration of the gas on the liquid surface increases, so that more gas molecules enter the liquid surface than those that escape from the liquid excitation surface, thus increasing the solubility of the gas. In addition, the solubility of the gas and the pressure (partial pressure) of the gas are in a positive light-and-eliminate ratio within a certain range (provided that the gas does not chemically change with water).

For example, in 20

, the pressure of hydrogen is 101

kpa, hydrogen at 1

The solubility in the water is.

l；Also in 20, in 2 101

kpa, hydrogen at 1

The solubility in the water is.

l×2＝l。

The greater the pressure, the greater the solubility, and the smaller the retort This is a bit like stuffing cotton into a bottle, the harder you push it, the more you stuff it. The distance between the gas molecules is relatively large, and they are connected by a weaker molecular force, if the applied force (pressure) can reduce their distance. The number of molecules of the same volume of gas is different, and the natural gas dissolved in the same volume of liquid (or other) is larger.

In the same way, the increase in temperature may cause the gas molecules to gain energy to make the internal movement of the molecules intense, and the space for molecular activity is larger than the original, that is, the volume increases. The larger the volume is larger, the lower the solubility.