giúp tớ với, mình học lớp 9 ạ

Gip T Vi, Mnh Hc Lp 9

Answers

Answer 1

Answer: broooo what is this

Explanation:


Related Questions

Write the empirical formula for at least four ionic compounds that could be formed from the following ions: NO3, Pb^4+, NH4, SO4

Answers

Explanation:

here's the answer to your question

double arrow just mean that it's a reversible process, and the reaction can go back and forth.

A 1.732 g sample of iron is heated in air. It oxidizes to form a product with a mass of 2.205 g.
What is the empirical formula of the product?

Answers

Answer:

A 1.732 g sample of iron is heated in air. It oxidizes to form a product with a mass of 2.205 g. What is the empirical formula of the product? FeO 4. Caffeine is made of 49.48% carbon, 5.19% hydrogen, 28.85% nitrogen, and 16.48% oxygen by mass.

Explanation:

The empirical formula of the product formed by the reaction of iron and oxygen is FeO.

Let's consider the following generic chemical equation:

Fe + O₂ ⇄ FexOy

According to the law of conservation of mass, the sum of the masses of the reactants is equal to the sum of the masses of the products. The mass of O₂ that reacted, and remains in the oxide is:

[tex]mFe + mO_2 = mFexOy\\mO_2 = mFexOy - mFe = 2.205 g - 1.732 g = 0.473 g[/tex]

The oxide has 1.732 g of Fe and 0.473 g of oxygen and a total mass of 2.205 g. To determine the empirical formula, we need to calculate the percent composition.

[tex]\%Fe = \frac{mFe}{mFexOy} \times 100 \% = \frac{1.732 g}{2.205 g} \times 100 \% = 78.55\%[/tex]

[tex]\%O = \frac{mO}{mFexOy} \times 100 \% = \frac{0.473 g}{2.205 g} \times 100 \% = 21.45\%[/tex]

Now, we will divide each percentage by the atomic mass of the element.

[tex]Fe: 78.55/55.85 = 1.406\\O: 21.45/16.00 = 1.340[/tex]

Finally, we divide both numbers by the smallest one.

[tex]Fe: 1.406/1.340 \approx 1 \\O: 1.340/1.340 = 1[/tex]

The empirical formula of the product is FeO.

You can learn more about empirical formulas here: https://brainly.com/question/1363167

list three factors that affect the rate of a chemical reaction

Answers

Answer:  1)  temperature, 2) add a catalyst, and 3) concentrations

Explanation:  A rise in temperature adds kinetic energy to the reactants, leading to more frequent, and energetic collisions, which will often accelerate the reaqction.  A catalyst is an agent that helps the reaction move forward more quickly by offering a substrate that aids in orienting the reactants for more efficient reaction.  A higher concentration increases the chances of collisons that result in products.

Which of the following describes scientists?
О
A. People with only one perspective
B. People with similar personalities
C. People from different backgrounds
D. People with perfect understanding of science

Answers

I believe the answer I’d D

Hope it helps

PLZ HELP ME A girl throws a ball and her dog chases it. What characteristic of living things is this dog demonstrating as it chases the ball?
A. Cells
B. Reproduction
C. Growth
D. Response ​

Answers

I'm not sure but I think its D.response

Some species form social groups only with members of the same gender. For example, elephants form groups with
only females and their offspring. Once the male offspring reach a certain age, they leave the group and become
solitary.
Which is a benefit of this type of social group structure?

Answers

Explanation:

For example, elephants form groups with only females and their offspring. Once the male offspring reach a certain age, they leave the group and become solitary. Which is a benefit of this type of social group structure? A:Females do not have to compete for a mate.

which chloride is a coloured solid rtp

Answers

Answer:

sodium chloride

hope that helped :)

Answer:

Chlorine is a greenish yellow gas at room temperature and atmospheric pressure. ... yielding chlorine water, and from this solution a solid hydrate of ideal ...

Which elements on the periodic table are the least reactive? (1 point)
o the group with helium at the top
the group with hydrogen at the top
the group with carbon at the top
the group with fluorine at the top

Answers

The group with helium at the top because those are the noble gases

Answer:

the group with helium at the top

Explanation:

I just took it

How many moles of oxygen are required to react completely with 5 mol C8H18?

Answers

Answer:

62.5 moles of O₂.

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

2C₈H₁₈ + 25O₂ —> 16CO₂ + 18H₂O

From the balanced equation above,

2 moles of C₈H₁₈ reacted with 25 moles of O₂.

Finally, we shall determine the number of mole of O₂ needed to react with 5 moles of C₈H₁₈. This can be obtained as shown below:

From the balanced equation above,

2 moles of C₈H₁₈ reacted with 25 moles of O₂.

Therefore, 5 moles of C₈H₁₈ will react with = (5 × 25) / 2 = 62.5 moles of O₂.

Thus, 62.5 moles of O₂ is needed for the reaction.

The number of joules required to heat one gram of a substance one degree Celsius is _____.


endothermic

temperature

exothermic

specific heat capacity

Answers

The answer is D - specific heat capacity.

hii pls help me to balance the equation thanksss​

Answers

Explanation:

2KCLO3 (s) = 2KCl (s) + 3O2 (g)

what is the product of SO2+H2O. ​

Answers

Answer:

H2O + SO2 → H2SO3

Explanation:

H2O + SO2 → H2SO3

Answer:

l think this is the answer .

A new stable element with an atomic number of 120 and an atomic mass of 246 is created in a particle accelerator. Enough of this element is created to determine that it combines with chlorine in a 1:2 ratio. Element 120 should be placed in the same group as _____ on the periodic table.

Answers

Answer:

Be,Mg,Ra etc

Explanation:

It should be palced in group 2A because as it reacts with chlorine in ratio of 1:2 . It's valancy is 2 and is metal as it react with non metal donating two electrons .

one more thing it fits there orderly

can you solve this science question ⁉️​

Answers

Answer:

chemical reaction between those a b c it's a reaction which occurs when heating

what is the name of this organic molecule

Answers

Answer:

C2H4 Ethylene

Explanation:

Hope it helps! :)

Sarah measures out 151 grams of SO2. How many moles is this? Express your answer to three significant figures.

Answers

Answer:

[tex]\boxed {\boxed {\sf 2.36 \ mol \ SO_2}}[/tex]

Explanation:

We are asked to convert grams to moles. We will use the molar mass and dimensional analysis to perform this conversion.

1. Molar Mass

The molar mass is the mass of 1 mole of a substance. These values are found on the Periodic Table because they are equivalent to the atomic masses, but the units are grams per mole instead.

We are given a mass of sulfur dioxide (SO₂). Look up the molar masses of the individual elements.

Sulfur (S): 32.07 g/mol Oxygen (O): 15.999 g/mol

Notice that the formula of the compound contains a subscript. The subscript after O means there are 2 moles of oxygen in 1 mole of sulfur dioxide. We must multiply oxygen's molar mass before adding sulfur's.

O₂: 15.999 * 2 = 31.998 g/mol SO₂= 32.07 + 31.998 = 64.068 g/mol

2. Convert Grams to Moles

Now we will use dimensional analysis to convert grams to moles. From the molar mass, we know there are 64.068 grams of sulfur dioxide per mole, so we can set up a ratio.

[tex]\frac {64.068 \ g \ SO_2} {1 \ mol \ SO_2}[/tex]

We are converting 151 grams to moles, so we multiply by this value.

[tex]151 \ g \ SO_2 *\frac {64.068 \ g \ SO_2} {1 \ mol \ SO_2}[/tex]

Flip the ratio so the units of grams of sulfur dioxide cancel.

[tex]151 \ g \ SO_2 *\frac {1 \ mol \ SO_2}{64.068 \ g \ SO_2}[/tex]

[tex]151 *\frac {1 \ mol \ SO_2}{64.068 }[/tex]

[tex]\frac {151}{64.068 } \ mol \ SO_2[/tex]

[tex]2.356870825 \ mol \ SO_2[/tex]

3. Round

The original measurement of grams (151) has 3 significant figures, so our answer must have the same. For the number we calculated, that is the hundredth place. The 6 in the thousandth place tells us to round the 5 in the hundredth up to a 6.

[tex]2.36 \ mol \ SO_2[/tex]

151 grams of sulfur dioxide is approximately 2.36 moles of sulfur dioxide.

Suppose you had a valuable collection of small diamonds, which you kept safe from the thieves by mixing them with white sugar crystals. You store the mixture in a jar labeled 'sugar'. Now you want to sell the diamonds. Describe how you would separate all the diamonds from the sugar.

Answers

Answer:

Pour the sugar/diamond mixture into a container of water and stir until the sugar is dissolved completely. Then strain the mixture and wash the diamonds with water.

Answer:

Stir with a large enough volume of cold water to dissolve all the sugar. Filter to leave the diamonds on the filter paper. Wash on the filter paper with more water to remove any last traces of sugar solution. Allow to dry.

5+64
this is TOTALLY SOOOO hard so help me
^thats what she said

Answers

Answer:

69

Explanation:

I thought that I answer is correct

Answer:

The answer is 69

Explanation:

Because if you add one its 66, and so on, hope this helps! but if you add five it will be 69, if you need help with easy equations let me know

name some examples of chemical solutions and maybe give a clear explanation as to what chemical solutions are ​

Answers

Answer:

Some examples of solutions are salt water, rubbing alcohol, and sugar dissolved in water. ... In our example of salt water, the solute is the salt. Solvent: this is the substance that makes up the majority of the solution. This is the part where the solute is dissolved.

Explanation:

I hope they should be right answer

Define force and speed​

Answers

Force = The external energy that changes or tends to change the state of any body or object is called force.

Speed = The rate of distance is called speed.

Answer:

Force is a push or pull which changes or tend to change the position of a body.

The rate of change its position with time or magnitude is called speed.

What is an atomic mass unti

Answers

Explanation:

a unit of mass used to express atomic and molecular weights, equal to one twelfth of the mass of an atom of carbon-12.

Answer:

Atomic Mass Unit is also called Dalton. It is used to express atomic and molecular weight. It is defined as 1/12 of the mass of an unbound neutral atom of carbon.

what is the reactant(s) in the chemical equation below

3CO(g) + Fe2O3(s) 2Fe(s) + 3CO2(g)

Answers

Answer:

the reactants are carbon dioxide ,iron, oxygen

Describe the formation of oxygen molecule​

Answers

Answer:

oxygen molecule has two oxygen atom . Each O atom share 2 electrons to form two covalent bonds out of which one is sigma bond and other is pi bond . sigma bond is formed by axial overlap 2p atomic orbitals of oxygen and pi bond is formed of lateral overlap of 2p atomic orbitals of oxygen .

What is the name for the compound li2so4

Answers

Answer:

Explanation:

Lithium Sulphate

Answer:

Lithium sulfate is a white inorganic salt with the formula Li2SO4. It is the lithium salt of sulfuric acid.

Small quantities of spilled acids can be made safe with *
1 point
o gasoline.
alcohol.
water.
sodium bicarbonate solution.

Answers

Answer:

sodium bicarbonate solution

What is the correct clases for this drugs

‏Compazine
heelp me please

What is the answer to 9.7300x10^2+9.8700x 10^3 1.0843x 10^ in scientific notation

Answers

Explanation:

Your search - What is the answer to 9.7300x10^2+9.8700x 10^3 1.0843x 10^ in scientific notation - did not match any documents.

Suggestions:

Make sure that all words are spelled correctly.

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Question 14 (Essay Worth 10 points) (03.05 MC) Use complete sentences to differentiate between acids and bases on the basis of touch. Give an example of each type.​

Answers

Answer:

Acid is a molecule capable of donating hydrogen ion and they form aqueous solutions with a sour taste while base is a substance that accepts proton from proton donor and in aqueous solution, they have an astringent or bitter taste. Moreover, a good example for base is sodium hydrogen carbonate as baking soda or baking powder and for acid, the most common example is the acetic acid or vinegar.

Answer:

Well, for starters, bases mostly consist of soaps and cleaning products, acids consist of vinegar,lemon,and stuff like that. Most acids on the basis of touch can burn your skin or be very sour, unlike bases which are more soapy and have a cleaner touch.A good example of an acid is vinegar, which can be used for cleaning but can also be used for making foods, on the other hand. A good example of a base is dish soap. It is used for cleaning.

Explanation:

i just did the exam and got a 100

Which of the following is a scientific question you could ask about the game
of basketball?
A. Do you enjoy basketball more than volleyball?
B. Which team is this year's best?
C. Which player should be traded to another team?
D. Do teams that practice more win more games?
SUBMIT

Answers

The scientific question related to the game of basketball is option D: "Do teams that practice more win more games?"

This question is scientific because it explores a cause-and-effect relationship between practice and game outcomes. It can be investigated through empirical observation and data analysis.

To answer this question, researchers could collect data on the practice hours of different basketball teams and compare them to their corresponding game performance. Statistical analysis could be used to determine if there is a correlation between practice time and winning percentage or other performance metrics.

By examining a large sample of teams over an extended period, researchers could draw conclusions about the impact of practice on game outcomes. This scientific inquiry would contribute to the understanding of the factors that influence team success in basketball and could potentially inform training strategies and coaching techniques.

For more question on basketball

https://brainly.com/question/29505871

#SPJ8

PLZ HELP ME WITH MY WORK
What is a compound?
A substance that is made from two different metals
B. A substance that cannot be broken into simpler substances
C. A substance that is made using a chemical reaction
D. A substance that can be separated by physical means​

Answers

Answer:

C.

Explanation:

Answer A is incorrect because a compound doesn't have to be made with only metals.

Answer B is incorrect because that is actually the definition of a pure element.

Answer C is correct because to make a compound, there has to be a chemical reaction where bonds are formed and an entirely new substance is created.

Answer D is incorrect because compounds cannot be separated by physical means.

Hope this helps :D

9. During an experiment the students prepared three mixtures A)Starch in water B) Sodium chloride solution C) Tincture of Iodine. i) Students observed a visible beam of light through mixture A. Why? ii) Tincture of lodTe did not show Tyndall effect. Explain reason. ill) How can you relate particle size to Tyndall effect?​

Answers

Answer:

See explanation

Explanation:

Tyndall effect refers to the scattering of light in a solution. Tyndall effect occurs when the size of particles in the solution exceeds 1 nm in diameter. Such solutions are actually called false solutions.

In tincture of iodine, the size of particles in solution is less than 1 nm in diameter hence the solution does not exhibit Tyndall effect. Hence, tincture of iodine is a true solution.

Therefore, if the size of particles in solution exceeded 1nm in diameter, Tyndall effect is observed.

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