Express in scientific notation. Choose the answer with the proper number of significant figures. 9x10^9/4.5x10^1​

Answers

Answer 1

Answer:

Your answer should be 2.4 x 10^9.  please hit the crown

Explanation:


Related Questions

a balloon initially has 0.40 liters and a temperature of 20°C what will the volume of the balloon be after it heats to 250°C

Answers

Answer:

0.7L

Explanation:

Given parameters:

Initial volume V₁  = 0.4L

Initial temperature T₁  = 20°C  = 20 + 273  = 293K

Final temperature  = 250°C  = 250 + 273  = 523K

Unknown:

Final volume V₂ = ?

Solution:

To solve this problem, we apply Charles's law.

It states that "the volume of a fixed mass of a gas varies directly as the absolute temperature if the pressure is constant".

 mathematically;

        [tex]\frac{V_{1} }{T_{1} } = \frac{V_{2} }{T_{2} }[/tex]  

V and T are temperature values

1 and 2 are initial and final states;

  Insert the parameters and solve;

   [tex]\frac{0.4}{293}[/tex]   = [tex]\frac{V_{2} }{523}[/tex]  

        V₂   = [tex]\frac{523 x 0.4}{293}[/tex]   = 0.7L

       



2. What properties do all acids have?

3. Why should you never use taste as a method for testing an unknown substance?

4. What is used to detect the presence of acids?

10. What can you use to detect the presence of a base?

11. What are some common bases that we use every day?

12. How does an antacid help reduce heartburn?

13. What happens when acid and base are mixed

14. What is used to determine the pH of a substance?

15. Describe how the pH scale works. In other words, what is it actually measuring?

17. Why is pH important to our environment?

18. Describe how salt is formed.

Pls help!!!!!

Answers

2. They taste sour, are electrolytes, and react with active metals to produce hydrogen.

3. You should NEVER taste unknown chemicals because many are poisonous and can destroy body tissue.

4. Most often dyes are used to detect acids. The dyes will turn a certain color which indicates the presence of an acid.

10. You can use litmus to detect wether a solution is a base or an acid.

11. The most common bases I can think of would be: baking soda, laundry detergent, or soaps.

12. Antacids work by neutralizing the acids in your stomach.

13. When an acid and base are mixed together, they produce a salt.

14. Normally pH meters are used, but you can also calculate the pH using math. (yuck)

15. The pH scale measures how acidic or basic a substance is. It ranges from 0-14, with 7 being neutral.

17. pH is very important to the environment as it helps us measure and monitor for safe water conditions. A rise or fall from the average water pH level can indicate chemical pollution.

18. Salt is formed when an acid and base react with each other. It then has a cation of the base, and anion of the acid.

I hope those helps!! (:

What historical data from Tokyo could have helped in the development of tokyo's new flood protection system?

Answers

Answer: This historical data could have helped with the development of Tokyo’s new flood protection system:

historical frequency of flooding

amount of flooding during each storm

computer models forecasting the worst possible flooding

Explanation:

The frequency of flooding can help Tokyo measure when the next flood will be.

The amount of flooding can help Tokyo determine how much water will come during the flood.

And computer models forecasting the worst possible flood can help reach out to people and tell whether they need to evacuate or what  they should plan for.    

Please help!!!! This equation is balanced: CaCO3 - CaO + CO2
True
False

Answers

Answer: false

Step by step explanation

3. Does the siren of a moving police car seem to change pitch to the
police officers inside the car? Why or why not?

Answers

Answer:

As the police car moves towards them, the pitch of the police car's siren goes up because the sound waves get closer together in front of the police car. When the police car moves away from the person, the pitch goes down because the waves spread out behind the police and that makes the frequency go down.

Explanation:

2 of 4
+ Automatic Zoom
10. The molar mass of CS2 is 76.14 g/mol. How many grams of CS2 are present in 10.00 mol?

Answers

Answer: C

Explanation:

There are 761.4 grams of CS2 in 10.00 mol.

To calculate the amount of grams present in a given amount of moles, the molar mass of the substance must be used, as follows:

                                        [tex]m = MM \times mol[/tex]

In this way, just perform the following operation:

                           

                                          [tex]m = 76.14 \times 10[/tex]

                                         [tex]m = 761.4 grams[/tex]

Thus, there are 761.4 grams of CS2 in 10 mol of the substance.

Learn more about mole calculation in: brainly.com/question/15693285

If all objects masses are the same, then the object with the least ___ is the densest?

Possible Answers:
A: Mass
B: Volume
C: Weight
D: Density

Answers

It’s either A or B, Sorry, I’m really not sure..

Answer:

its weight

Explanation:

mass is how much space it takes up the volume stays the same density is what happens after so its weight

(Need Help ASAP) 23.5 grams of iron(III) oxide (Fe2O3) are reacted with excess carbon. What is the theoretical yield of iron metal?

2 Fe2O3 + 3 C --> 4 Fe + 3 CO2

Answers

The theoretical yield of iron metal : 16.418 g

Further explanation

A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.

Reaction

2 Fe₂O₃ + 3 C ⇒ 4 Fe + 3 CO₂

mol Fe₂O₃ (MW=159,69 g/mol) :

[tex]\tt \dfrac{23.5}{159.69}=0.147[/tex]

mol  Fe₂O₃ : mol Fe = 2 : 4

mol Fe :

[tex]\tt \dfrac{4}{2}\times 0.147=0.294[/tex]

mass Fe(the theoretical yield) :

[tex]\tt 0.294\times 55.845~g/mol=16.418~g[/tex]

Answer:

The correct answer with signfigs is 16.4 for the first part

The second box is 88.4

Explanation:

You are doing math homework and get frustrated and throw the 7 kg book with a force of 47
Newtons. How much acceleration will the book have when you throw it?

Answers

Answer:

The answer is 6.71 m/s²

Explanation:

The acceleration of an object given it's mass and the force acting on it can be found by using the formula

[tex]a = \frac{f}{m} \\ [/tex]

f is the force

m is the mass

From the question we have

[tex]a = \frac{47}{7} \\ = 6.714285...[/tex]

We have the final answer as

6.71 m/s²

Hope this helps you

Cream from milk can be separated by
process ......................................​

Answers

Answer:

centrifugation

Explanation:

TIMED CHEMISTRY PLZ HELP How many selenium atoms are in the chemical formula for the compound formed when selenium is combined with lead(II)?

Answers

Answer: Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal with properties that are intermediate between the elements above

Explanation:

at least three everyday things that exist or occur because of science.

Answers

Answer:  

1.A POWER DRILL COULD SET YOUR HOUSE ON FIRE, IN THEORY.

2.STICKY NOTES COME OFF EASILY BECAUSE THEIR ADHESIVE IS UNEVEN. ...

3.GUM IS CHEWY BECAUSE IT'S MADE OF RUBBER. ...

4.OFFICE BUILDINGS ARE EVER-SO-SLIGHTLY TALLER AT NIGHT. ...

5.A LEGO BRICK CAN SUPPORT 770 POUNDS OF FORCE. ...

6.POLISHING SHOES IS LIKE FILLING IN A ROAD'S POTHOLES.

Explanation:

Can someone help? Ill give brainliest!

Directions: count each side of the reaction. Circle yes or no if it follows the law of conservation of mass

Answers

Answer:

Yes, it becomes 2 of H20 which is water

Can someone help me plz for BRAINLIST I swear I’ll give it to you !! I’m in 6th grade ( just started ) please help I’m begging !!

Answers

Answer:

Lithium                    Li                        3                 3                 4

Titanium                Ti                        22               22               26

Cobalt                   Co                      27                27               32

Silicon                    Si                       14                 14                14

Platinum                 Pt                      78                 78               117

Bromine                 Br                      35                 35               45

Nickel                     Ni                     28                  28               31

Manganese            Mn                   25                    25             30

Boron                      B                       5                     5                6

Oxygen                   O                       8                     8                8

Zinc                         Zn                      30                  30             35

Lead                        Pb                      82                   82            125

Explanation:

Can I have brainliest? This took me like an hour to find the answers and type the answers. TYSMMMMMMMMMMMMMMM  

Edit: I am also in 6th grade, but I looked it up because I haven't learned this yet.

Why should a hypothesis be testable?
A. It must be testable in order to be found true or false.
B. It must be testable for the outcome to be predictable.
C. It must be testable for other scientists to consider it reliable.
D. It must be testable if it is to become a scientific theory.

Answers

A. It must be testable in order to be found true or false.

If, in the reaction below, 49 grams of Fe3O4 produces a 78.25% yield of Fe. How many grams are produced?

Really need help on this please, I’ll give brainliest!!

Answers

Only 10 jdjsjkslqms xmcmdlslsllxndmwlzodod
Only 10 grams are produced!

One isotope of oxygen differs from another isotope of oxygen in *

Answers

Each isotope of Oxygen has a different number of neutrons

Further explanation

The elements in nature have several types of isotopes

Atomic mass is the average atomic mass of all its isotopes

Isotopes are atoms has the same number of protons but has a different number of neutrons.

So Isotopes are elements that have the same Atomic Number (Proton)

Some of the isotopes of oxygen are:

[tex]\tt _8^{16}O,_8^{17}O,_8^{18}O[/tex]

Each isotope has 8 protons and 8 electrons but has a different number of neutrons

For O-16: number of neutrons = 16-8 = 8

For O-17: number of neutrons = 17-8 = 9

For O-18: number of neutrons = 18-8 = 10

secondary alcohol (X) reacts with PCL5 to give alkyl halide (Y) which on dehydrohalogenation yield an alkene(Z).The alkene upon ozonolysis gives the mixture of ethanal and methanal.Identify X ,Y ,Z​

Answers

Answer:

X = 2-propanol

Y = 2-chloropropane

Z = propene

Explanation:

Secondary alcohol is an alcohol in which the carbon that the functional group (OH group) is attached to is also attached to two alkyl group. Examples are 2-propanol and 2-butanol.

The secondary alcohol referred to in the question here is 2-propanol and it reacts with PCl₅ as seen below

H₃C-CH-CH₃ + PCl₅ ⇒ H₃C-CH-CH₃ + HCl + POCl₃

        |                                     |

       OH                                Cl

The alkylhalide produced there is 2-chloropropane. Thus, we can see that X is 2-propanol and  Y is 2-chloropropane.

When this 2-chloropropane undergoes dehydrohalogenation (removal of hydrogen and halogen) an alkene is formed. The reaction is seen below

H₃C-CH-CH₃   (-HCl)    ⇒  H₃C-CH=CH₂

        |

       Cl

The alkene produced (as seen above) is propene.

Confirmation: When propene undergoes ozonolysis, the compounds produced are ethanal and methanal as seen in the equation below

                                                   O

                                                 /    \

H₃C-CH=CH₂ + O₃  ⇒  H₃C - CH  CH₂    [-O]  ⇒ CH + CH₂  

                                                 ||     ||                     ||        ||

                                                O    O                    O      O

The final products as seen above are methanal and ethanal

I need help pretty bad can you answer all these questions

Answers

DIFFERENCE BETWEEN BIOTIC AND ABIOTIC

abiotic are non living things and biotic are living beings

Eukaryotic:these are developed

and complete cells with well developed nucleus

PROKARYOTIC:these are primitive and incomplete cells without well developed nucleus difference between autotrophs and heterotrophs AUTOTROPHS :

these are the organism which make their own food by photosynthesis

Heterotophs :

these are the organism which depend on other organism for food

KINGDOMS:

Monera

Protista

fungi

plantae

animalia

TAXONOMY IS the branch of biology that deals with the identification,nomenclature and classification of organism

2. How can glass be a liquid if it's so hard?

Answers

Explanation:

Glass is not a liquid in the strictest sense of the word. But it is also not a standard solid. The chemistry of glass is complex and research is ongoing, but the current consensus is that glass is a phase of matter all its own, known as an "amorphous solid". Scientists refer to any amorphous solid as a "glass". Glass transitions are highly complex and cannot be treated in the same way as traditional phase transitions.

Answer:

It's a liquid state before its cooled.

Someone tell me if I did the equation correctly or not.
Reaction between aqueous Washing soda and lemon juice=
3Na2Co3 + 2C6H8O7 = 2Na3(C6H3O7)+3CO2 (g) + 3H2O(l)


Answers

Hey There!_____________________________________Answer:

Washing Soda:

Sodium Carbonate commonly known as Sodium Carbonate is a inorganic compound which used in detergents and to soften the water. Its chemical formula is [tex]Na_{2}CO_{3_[/tex]. It is carbonate base

Lemon Juice:

Lemon juice contain citric acid whose chemical formula is [tex]C_{6} H_{8} O_{7}[/tex]. Citric acid is a weak organic acid thus It is used for disinfectants and cleaning as well.

_____________________________________Reaction b/w Washing Soda and Citric Acid

When Lemon Juice and Washing Soda react, the reaction is just an acid-base reaction and forms trisodium citrate and carbonic acid. The latter is then dissociated into Carbon Dioxide and Water. Carbon Dioxide escapes in the form of bubbles and Sodium Citrate(salt) and Water behind.

(citric acid)+ (sodium carbonate)= (trisodium citrate)+(water)+(carbon dioxide)

                                 OR

            [tex]2C_{6}H_{8}O_{7} + 3Na_{2}CO_{3} ---> 2Na_{3}(C_{6} H_{3} O_{7})_{2} + 3H_{2}O + 3 CO_{2}[/tex]

_____________________________________Best Regards,'Borz'

help me solve. this is science. Which one is it

Answers

Answer:

d is the correct answer i think

HELP!!!
i will mark brainliest ​

Answers

Answer:

Blank #1: noble gas

Blank #2: bonding

Blank #3: octet rule

Blank #4: share

Blank #5: filled

Blank #6: halogen

Please give me brianliest!!

Procedure: Step by step- what procedures should be followed while making the colors of the different fireworks (the shells and launch mechanisms will be made by the physics and design classes) the colors are: silver, white, gold and pink plz i need help ​

Answers

Answer:

It chemistry babe

Explanation:

4. Imagine you have a radioactive sample containing both Virtualium and decayed atoms of Virtualium. After analysis, you find it contains 10 atoms of Virtualium and 40 decayed atoms. How old is your sample? (Hint: You must use the half-life of Virtualium determined earlier in the activity.)

Answers

Answer:

25

Explanation:

Three friends were kicking soccer balls at a neighborhood field. Three soccer balls were rolling across the field. The black soccer ball has less mass than the blue and orange balls, which have equal mass. All three soccer balls were kicked by one of the friends, but not all from the same direction. Use the information in the diagram to answer.


Which soccer ball(s) experienced the strongest force? How do you know?

A. All three soccer balls experienced the same force because they changed speed by the same amount.

B the orange soccer ball it has more mass and the fastest ending speed

c. the blue soccer ball it takes a stronger force to slow down a more massive object than to speed it up.

D the blue and orange soccer balls they have more mass than the black soccer ball changed speed by the same amount

Answers

Answer: d :The blue and orange soccer balls; they have more mass than the black soccer ball, but changed speed by the same amount.

Answer:

the answer is d

Explanation:

A student made 50g of sodium acetate , 20g of water and 15g of carbon dioxide by reacting baking soda with vinegar. How many total grams of baking soda and vinegar did the student react?

Answers

Answer:

Reacting of 5 cm3 of baking soda with 100 cm3 of vinegar should produce 0.083 moles of CO2 gas, 0.083 moles of sodium acetate, and leave 0.01 moles of sodium bicarbonate unreacted.

Explanation:

Substance A dissociates 100% in water to produce H3O+ ions while substance B dissociates 25% in water to produce OH- ions. What can be determined from this information?
A:Substance A is a strong acid and substance B is a weak base
B:Substance A is a weak acid and substance B is a strong base
C:Substance A is a strong base and substance B is a weak acid
D:Substance A is a weak base and substance B is a strong acid

Answers

Answer:

A:Substance A is a strong acid and substance B is a weak base

Explanation:

From this information, we can conclude that substance A is a strong acid and substance B is a weak base.

A strong acid is one that ionizes completely in solution. Most strong acids are usually concentrated. 100% dissociation is a complete ionization.

A weak base ionizes slightly in an aqueous solution. 25% dissociation is weak ionization.

Answer:

a

Explanation:

Which of the following does not apply to water molecules?

Water molecules are polar
Water has cohesive properties
Water is less dense as a solid than a liquid
Water is not a very good solvent

Answers

Answer:

It is the last one.

Explanation:

Water molecules are polar, they have cohesive properties, and water is less dense when it is solid than when it is a liquid, that is why ice floats in liquid water. However, water is a very good solvent, it can dissolve many solids, including sugar, salt, and other hydrophilic substances.

Sodium hydrogen carbonate and citric acid

Word equation

Answers

Answer:

the right answer is:

Explanation:

How to Balance: NaHCO3 + HC2H3O2 = NaC2H3O2 + CO2 + H2O|

Answer:

NaHCO3 +C6H8O7

Explanation:

these are the formulas of sodium hydrogen carbonate and citric acid

Other Questions
. How many 0.5-liter glasses of water can be poured from a full 6-liter pitcher? HELPP If you are sitting on a stationary bus, which frame of reference might make you think the bus has started moving? a. A car in the next lane passes the bus. b A passenger moves to the back of the bus. c The bus driver turns to look through the windshield. scd None of the above. Please help me, will mark you as brainiest! Dont answer if you dont know it! solve 2x to the second power - 8x = -7 Round 8250 to the nearest hundred. A model of Earths water budget shows that the precipitation on oceans is 420,000 km3 and the precipitation on land is 130,000 km3. If the evaporation from land is 90,000 km3, how much is the evaporation from oceans? Jane is helping the librarian stack books on some new shelves. She is to stack 116 books on 16 shelves. The librarian told her to put the same number of books on each of the 16 shelves. Can Jane put the same number of books on each shelf? Explain why or why not. O C. mitochondria 2. Where is the major site of photosynthesis in a plant? * O A. the stem O B. the roots O C. the leaves Nancy lives with her mom. Her mom is a single mom who works long hours. Nancy feels like the foodthat they have in the house isn't very healthy and she wants to eat a better diet. What are some thingsthat Nancy could do? what do you mean by the determinant of birth Which of the following is the correct formula For aluminum oxide?A.AIOB.AI3O2C.OAID.AI2O3 Completely factor the expression. Which amendment guarantees citizens' right to due process?A. the first amendmentB. the fifth amendment C. the fourth amendmentD. the sixth amendment Which biomolecule provides the instructions to build enzymes?A. CarbohydratesB. LipidsC. Nucleic acidsD. Proteins I WILL MARK YOU BRAINLIEST PLEASE HELP. It needs to be correct What is the result of 4 divided by one-half? A number line going from 0 to 4. 2 8 12 16 Do you think the cartoonist believes that Andrew Carnegie is a hero? Explain. i cant figure out what 8 1/2-3/5 is equals WILL MAKE YOU BRAINLIEST FOR NO REASON IF YOU GIVE BEST RESPONSE Guys plz help answer this!!!!