Fill in the blanks in the first year of science, fill in the blanks in the first year of science

1.Rise 2Drop 3When a substance dissolves, it needs to absorb heat.

Explanation: When a substance dissolves, it needs to absorb heat, but when some substances are combined with water, they will absorb or produce heat due to the different properties of the substance.

No, because the sun's rays were blocked by the earth and couldn't reach the moon, so the moon couldn't reflect the sun's rays, so there was no light source, and there was no observation. Suggestion: It is better to observe the effect around the 15th of each month of the lunar calendar.

1.Take two beakers, fill them with some water, and use a thermometer to measure the water temperature to be the same. Then the sodium hydroxide was dissolved in a beaker, the ammonium nitrate was dissolved in a beaker B, and then measured with a thermometer, and the thermometer in a beaker was found to indicate (rising) and the thermometer in a beaker (decreasing).

The above experiments show that when a substance is dissolved, two changes occur, one is to absorb heat and the other is to release heat).

2.Xiao Ming and Xiao Qiang plan to observe the crater on the moon with Xiao Ming's newly bought astronomical telescope on the night of Chinese New Year's Eve, can they observe it? Do you have any good observations for them?

A: No, it is impossible to observe distant objects with ordinary telescopes, it is recommended to observe the crater of the moon, preferably at the planetarium.

1.Getting bigger and getting smaller There are two kinds of energy changes, one is the heat absorbed when the solute molecules diffuse, and the other is the heat released when the solute molecules combine with the water molecules to form hydrated molecules or hydrated ions.

2.No, because at the beginning of the month, the earth blocks the light from the moon, and the moon is a quarter moon that cannot be observed, so many astronomy enthusiasts do not observe it during the first quarter of the moon.

Obviously, when sodium metal reacts with water, the chemical bonds of the water molecules are opened, and a lot of heat is naturally released, not simply dissolved and diffused.

1.High and low are accompanied by changes in energy.

2.No, because there was no moon in the sky at that time.

Green. White.

Light. Towards the light.

Nature. Ecology.

1.High and low are accompanied by changes in energy.

2.No. Because there was no moon in the sky at that time, it should be observed around the fifteenth day of the lunar calendar, which is the full moon at this time.

power) m divided by 3 * 10 to the power of 8. Second.

(1) Write the chemical formulas of the following substances.

HCl HCl, H2SO4 sulfate, HNO3 nitrate

2) Hydrochloric acid, sulfuric acid, and nitric acid are all hydrogen ions when they are ionized, so they are all acids 3) According to whether there is oxygen in the acid, the acid can be divided into oxygenated acid and anaerobic acid

4) According to the number of hydrogen atoms contained in an acid molecule, acids can be divided into monobasic acids and dibasic acids

2.(1) Write the chemical formula of the following salts:

Sodium carbonate Na2CO3, barium chloride BaCl2, silver nitrate Agno3, copper sulfate CuSO4

2) Among the above-mentioned salts, the one that belongs to carbonate is Na2CO3 because it contains carbonate , and the one that belongs to sulfate is Cuso4 because it contains sulfate

3.There are four kinds of particles: OH-, H+, NO, and CU, (1) an acid that can be composed of H+ and NO3 - 2) a base that can be composed of OH- and Cu2+ 3) and a salt that can be composed of Cu 2+ and NO3 -

1.Salt: is a product of the neutralization reaction and is a compound composed of acids and bases.

2.Properties of Sodium Carbonate: (Chemical Formula:

Na2CO3) common name: soda ash soda white powder, soluble in water, aqueous solution alkaline, its crystal hydrate chemical formula is Na2CO3·10H2O easy to lose crystal water and become sodium carbonate powder, this process is called weathering

3.Properties of calcium carbonate: Chemical formula: CaCO3 is the main component of laboratory CO2, chemical equation: CaCO3+2HCl=CaCl2+H2O+CO2

4.Properties of Sodium Chloride: (Chemical Formula: NaCl) Common Name: Table Salt Normal saline is a concentration of sodium chloride solution, and concentrated brine has a disinfecting effect.

5.Properties of copper sulphate: (Chemical formula: CuSO4.)

1) White powder, blue when exposed to water, use: to check whether the substance contains water as an absorbent.

2) Copper sulfate solution is added dropwise to egg white to produce precipitation Use: Configure pesticide Bordeaux solution to sterilize and kill insects.

1.Sodium hydroxide solution is added to copper sulfate solution, and the experimental phenomenon is that there is a blue precipitate formation The relevant chemical equation is CuSO4+2NaOH=Cu(OH)2+Na2SO4

2.The crushed copper sulfate crystals were put into the test tube and heated, and the experimental phenomenon was that the crystals changed from blue to colorless, and the chemical equation was CuSO4·5H2O== ==CuSO4+5H2O

3.In a cooled test tube filled with copper sulfate, add a few drops of water, and the experimental phenomenon is that copper sulfate changes from white to blue Chemical equation CuSO4+5H2O=CuSO4·5H2O According to this property, you think that the use of copper sulfate is to test water

I haven't read chemistry for a long time, and I still have a perfect score on the high school diploma exam.

1.Produces a blue precipitate (sometimes a green precipitate.) But if you write this, the teacher will say that you are wrong! But the fact does there will be) CuSO4 + 2NaOH = Cu(OH)2 + Na2SO4

The following ones are too troublesome.

This is also posted Shame on you? ~！There are still people who answer

1. There is a blue solid precipitate.

CuSO4 + NaOH – Na2SO4 + Cu(OH)22, the blue crystal turns white, 3, the white turns blue.

Large and small water vapor dehydration absorbs water.

c2h4o3 b

Purple litmus. Sodium carbonate solution.

fe+h2so4=feso4+h2

na2co3+ca(oh)2=caco3+2naohnaoh+cucl2=naoh+cu(oh)2h2so4+ba(oh)2=baso4+2h2ocaco3+2hcl=cacl2+h2o

Large and small water vapor dehydration water absorption C2H4O3 B

Litmus solution

Sodium carbonate Na2CO3+Ca(OH)2=CaCO3+2NaohNaOH+CuCl2=NaOH+Cu(OH)2H2SO4+BA(OH)2=BaSO4+2H2OCAco3+2HCl=CaCl2+H2O-

1.On the nameplate of a 37-inch LCD TV"220v 200w", the TV consumes kilowatt-hours of electricity for 1 hour of normal operation.

2.There is a solar fan hat, the top of the hat is equipped with a solar panel, and the brim is equipped with a small electric fan. Under the irradiation of sunlight, the solar panel converts solar energy into electrical energy, which drives the electric fan to work.

The voltage of the electric fan is 50mA, and if the fan works normally for 1 hour, the current work is 270 joules.

3.Solar lights use solar panels to provide one"12v 9w"The electronic energy-saving lamps work. The current when this type of light normally emits light is , and the electrical energy it consumes is converted from solar energy.

If sunlight shines on the solar panel for one day, the electronic energy-saving lamp can shine normally for 10 hours, then the electrical energy provided by the solar panel is 324000 j

4.The lettering on the bulb L"pz 220v-40w"The meaning of the indication is that the rated voltage is 220V, the rated power is 40W, and the power consumption of this bulb is 720000 joules when it works normally for 5 hours.