what part of the scientific method involves drawing inferences about experimental results and determining if the collected data support the original hypothesis?
Answer:
Drawing Conclusions
Explanation:
You put together your observations and can finally decide if your hypothesis was right or not.
The protons and neutrons are in the nucleus of the atom, while the electrons are on the outside. How would you calculate the number of neutrons in an atom? Subtract the atomic mass and the atomic number. Add the atomic mass and the atomic number. Subtract the number of protons from the atomic number. Add the number of protons to the atomic number.
Suppose you wanted to calculate the heat of reaction for the formation of ammonia gas and hydrochloric acid from solid ammonium chloride. Write a balanced equation for this reaction
Answer:
NH4Cl (s) → NH3 (g) + HCl (aq)
The diagram shows a model of an animal cell. Explain how you'd modify the model to show the structures in a plant cell.
Answer:to show the structures of a plant cell,add a cell wall around the membrane and increase the size of the vaculoe insidethe cell, draw green ovals to represent chloroplasts.
Explanation:
How does an object's mechanical energy change as its speed (velocity) increases?
Answer:
The mechanical energy of the system increases, provided there is no loss of energy due to friction. The energy would transform to kinetic energy when the speed is increasing. The mechanical energy of the system remains constant provided there is no loss of energy due to friction.
Explanation:
Calculate the molarity of a NaOH solution that is prepared by diluting 100mL of 0.20M NaOH with 150mL of H2O.
Molarity of solution = 0.08 M
Further explanationMolarity shows the number of moles of solute in every 1 liter of solution or mmol in each ml of solution
[tex]\tt M=\dfrac{n}{V}[/tex]
Where
M = Molarity
n = number of moles of solute
V = Volume of solution
mol of NaOH[tex]\tt mol=0.2~M\times 100~ml=20~mlmol=0.02~mol[/tex]
molarityVolume of solution = 100 ml + 150 ml = 250 ml
[tex]\tt M=\dfrac{0.02~mol}{0.250~L}=0.08[/tex]
What is the volume of 25.3 g of silver if the density of silver is 10.5 g/mL?
Answer:
MARK AS BRAINLIST
Explanation:
density = mass/volume
mass=25.3
density =10.5
10.5=25.3/v
v=25.3/10.5
=2.40
Which of the following is an example of quantitative data?
A.five eggs in each nest
B.oval-shaped eggs
C.small eggs
D.blue eggs with white specks
Using the reaction below: 2 CO2(g) + 2 H2O(l) → C2H4(g) + 3 O2(g) ΔHrxn= +1411.1 kJ What would be the heat of reaction for this reaction? 0.5 C2H4(g) + 1.5 O2(g) → CO2(g) + H2O(l) ΔHrxn= ??? KJ Question 6 options: a) Not enough information is given b) -2822.2 kJ c) +1411.1 kJ d) -705.55 kJ e) -1411.1 kJ
Answer: d) -705.55 kJ
Explanation:
Heat of reaction is the change of enthalpy during a chemical reaction with all substances in their standard states.
[tex]2CO_2(g)+2H_2O(l)\rightarrow C_2H_4(g)+3O_2(g)[/tex] [tex]\Delta H=+1411.1kJ[/tex]
Reversing the reaction, changes the sign of [tex]\Delta H[/tex]
[tex]C_2H_4(g)+3O_2(g)\rightarrow 2CO_2(g)+2H_2O(l)[/tex]
[tex]\Delta H=-1411.1kJ[/tex]
On multiplying the reaction by [tex]\frac{1}{2}[/tex] , enthalpy gets half:
[tex]0.5C_2H_4(g)+1.5O_2(g)\rightarrow CO_2(g)+H_2O(l)[/tex][tex]\Delta H=\frac{1}{2}\times -1411.1kJ=-705.55kJ/mol[/tex]
Thus the enthalpy change for the given reaction is -705.55kJ
By what process do small molecules move into cells?
Answer:
small molecules move into the cell, Then it is by diffusion or facilliated diffusion.
Write the word equations for the following balanced chemical equations.
a. Zn + 2HCl → ZnCl2 + H2
b. 2503 2502 + O2
Answer:
21
Explanation:9+10
If 23,000 joules of energy are used to heat mercury by 4.00 °C, what is the mass of the mercury?
8.
188 W
188
75
Re
+
74
The statement means that in every interaction, there is a pair of forces acting on the two interacting objects. The size of the forces on the first object equals the size of the force on the second object. The direction of the force on the first object is opposite to the direction of the force on the second object. Forces always come in pairs - equal and opposite action-reaction force pairs.
Which scientist did people think was insane so they dismissed his ideas for almost 2000 years?
Silver is a white metal that is an excellent conductor. Silver tarnishes when exposed to air and light. The density of silver is 10.49 g/cm3. The melting point is 962oC and the boiling point is 2000oC. A chemical property of silver is A) density. B) melting point. C) tarnishes in air. D) that it is a conductor.
Answer:
c tarnishes in air
Explanation:
After silver has been exposed to air that contains sulphur gases, discoloration would occur. there would be darkening that is caused by the reaction with gases.When any silver object tarnishes, it brings about a disfiguring of that object. Hydrogen sulphide would be needed for this to happen. silver sulphide is black and a if a thin layer should form on any surface, it ill darken it. This is what we refer to as tarnishing.
Answer:
c
Explanation:
it tarnishes in air
The density of a pure liquid at 25 degrees Celsius was calculated by determining the mass and volume of a sample of the liquid. A student measured the mass of a clean, dry 25.00 mL volumetric flask, filled the flask to its calibration mark with the liquid, and then measured the mass of the flask and liquid. The recorded measurements are shown in the table above. On the basis of this information, to how many significant figures should the density of the liquid be reported?
Answer
The density of the liquid is 0.82 g/mL.
Explanation:
From the question given above, the following data were obtained:
Mass of empty flask = 18.990 g
Mass of flask + liquid = 39.439 g
Volume of liquid = 25 mL
Density of liquid =..?
Next, we shall determine the mass of the liquid. This can be obtained as follow:
Mass of empty flask = 18.990 g
Mass of flask + liquid = 39.439 g
Mass of liquid =.?
Mass of liquid = (Mass of flask + liquid) – (Mass of empty flask)
Mass of liquid = 39.439 – 18.990
Mass of liquid = 20.503 g
Finally, we shall determine the density of the liquid as follow:
Mass of liquid = 20.503 g
Volume of liquid = 25 mL
Density of liquid =..?
Density = mass / volume
Density of liquid = 20.503 / 25
Density of liquid = 0.82 g/mL
Which of these statements describes a chemical property?
Answer:
it rusts when exposed to air
Answer:
A
Explanation:
Describe the main differences beA human cell has 46 chromosomes. At the end of mitosis, there are two cells, each with 46 chromosomes, for a total of 92 chromosomes split between both cells.
Which statement describes meiosis in a human cell?
At the end of meiosis, there are two cells, each with 46 chromosomes, for a total of 92 chromosomes split between both cells.
At the end of meiosis, there are four cells, each with 23 chromosomes, for a total of 92 chromosomes split between the four cells.
At the end of meiosis, there are four cells, each with 46 chromosomes, for a total of 184 chromosomes split between the four cells.
At the end of meiosis, there are two cells, each with 23 chromosomes, for a total of 184 chromosomes split between both cells. tween meiosis and mitosis.
Answer:
At the end of meiosis, there are four cells, each with 23 chromosomes, for a total of 92 chromosomes split between the four cells.
Explanation:
During meiosis, a diploid cell (46 chromosomes) replicates its DNA (making 92 chromosomes) then undergoes two cell divisions to generate four haploid cells (23 chromosomes).
These haploid cells are the gametes which, during fertilization, fuse to become a zygote with 46 chromosomes.
Answer:
the person above me is correct.
Explanation:
How does the work needed to lift an object and the gravitational potential energy of the object compare? OThey are equal. OThe work is greater. OThe work is less. OThe comparison dependş on the height.
○ they are equal
○ the work is greater
○ the work is less
○ the comparison depends on the height
Answer:
They are equal
Explanation:
took the test
Answer:
ITS A JUST FINISHED
Explanation:
Using triangulation which point is the earthquakes epicenter?
Answer:
free points aye
Explanation:
Answer: 3
Three is where the earthquakes epicenter is.
Plz mark brainliest:)
You check the air pressure in your car tires on Monday morning and the pressure
reads 765 mmHg. A cold front drops the temperature considerably overnight. You
check your tire pressure Tuesday morning and the pressure reads 740 mmHg.
Using what you've learned about the properties of gases, what causes this change
in pressure?
A metal object has a density of 2 g/ml. When placed in a graduated cylinder with 500 ml of water, the
water rises to 508 ml. What is the mass of the metal object?
Answer:
The answer is 16 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volumeFrom the question
density = 2 g/ml
volume = final volume of water - initial volume of water
volume = 508 - 500 = 8 mL
We have
mass = 2 × 8
We have the final answer as
16 gHope this helps you
Radon-222 is an alpha emitter with a half life of 3.82 days.
1. What is the mass number of the daughter isotope?
2. What is the element symbol of the daughter isotope?
3. What is the atomic number of the daughter isotope?
The daughter isotope (a decay product): Polonium (Po)
Further explanationRadioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,
alpha α particles ₂He⁴ beta β ₋₁e⁰ particles gamma particles γ positron particles ₁e⁰
Radon-222 emits alpha α particles ₂He⁴ , so the atomic number decreases by 2, mass number decreases by 4
Reaction
[tex]\tt _{86}^{222}Rn\Rightarrow _{84}^{218}+_2^4He[/tex]
1. The mass number of the daughter isotope = 218
2 and 3. If we look at the periodic system, the element with atomic number 84 is Polonium (Po)
Help plzzzzz ASAP!!!!!!!
Answer:
3. The total number of protons and neutrons in an atom is its mass number.
4. The mass number of a helium atom with 2 protons and 2 neutrons is 4.
5. A beryllium atom with 4 protons and a mass number of 9 has 5 neutrons.
6. The chemical symbol is Ne. The atomic number is 10. The mass number is 22.
7. Neon-22
8. Not enough information
An object has 15 grams of atoms and displaces 2.5 mL of water when dropped into a cylinder. What is the objects density... HELP IM IN CLASS RN AND I NEED ANSWERS ASAP, grades are due in couple hours
Answer:
6g/mL
Explanation:
The density, which is the mass per unit volume of an object, can be calculated using the formula;
D= m/v
Where; D = density (g/mL)
M = mass of substance (g)
V = volume (mL)
In this question, the object's mass = 15g, volume of water= 2.5 mL, d =?
Therefore,
Density = 15/2.5
Density = 6 g/mL
The object's density is 6g/mL
Which landform is created by glaciers? A. sandbar B. moraine C. alluvial fan (will give brainliest to the best answer)
Answer: B: Moraine
Explanation:
Each of the four liquids had the same volume, why don’t
they each have the same density?
Key concepts
Physics
Chemistry
Density
Liquids
Introduction
You probably know that when solid objects are placed in liquid, they can sink or float. But did you know that liquids can also sink or float? In fact, it is possible to stack different layers of liquids on top of one another. The key is that all the different layers must have different densities. You can stack them by picking several liquids with a range of densities or by varying the density of one liquid by adding chemicals such as sugar or salt to it. If you choose colored liquids or add food coloring to each layer, you can even create a whole rainbow of colors in one single glass! Want to see for yourself? In this science activity you will stack several liquids—one by one—and create a colorful density column!
Background
Whether an object sinks or floats depends on its density compared with the density of the liquid into which it is dropped. All types of matter—solids as well as liquids—are made up of many different atoms. Depending on the mass of these atoms, their size and the way they are arranged, different substances will have different densities. The density is characteristic for each individual compound and defined as the mass of a compound divided by its volume. In other words, the more matter there is in a certain amount of volume, the denser a substance is. One cubic centimeter of rock, for example, is much heavier than a cubic centimeter of wood. This is because there is much more matter in the same volume of rock compared with the wood.
ADVERTISEMENT
Liquids can also have different densities. Freshwater, for example, has a density of about one gram per cubic centimeter at room temperature. Any compound—liquid or solid—that has a higher density than water will sink whereas substances with a lower density than that will float. You can test that for yourself by gathering several liquids that you have in your kitchen such as vegetable oil, corn syrup, dishwashing soap, water, rubbing alcohol and more. Which one of these do you think will sink or float in water? Find out in this activity!
Materials
Glass or cup
Water
Food coloring
Scissors
Rubber band (wide)
Small piece of wax
Popsicle stick
At least two small, clear jars or transparent mini cups (two ounces) with lids
Permanent marker
Masking tape
Three tablespoons
Dark corn syrup
Vegetable oil
Penny
Paper towels
Rubbing alcohol, dishwashing soap and other liquids (optional)
Sugar (optional)
Preparation
Gather all your materials at a workspace that can tolerate spills of all the liquids.
Fill a cup with tap water and add a couple of drops of food coloring to the water.
Ask an adult to help you cut and prepare small pieces (about 0.5 by 0.5 centimeter) of the rubber band, the popsicle stick and the wax.
Place the two empty jars in front of you (without the lids) and label them “1” and “2” with a piece of tape and the permanent marker.
Procedure
Take a clean tablespoon and pour two tablespoons of corn syrup in jar 1.
With the second tablespoon, carefully pour two tablespoons of colored water into jar 1 on top of the corn syrup. What happens to the water on top of the corn syrup? Does it mix or stay separate?
Use the third clean tablespoon to pour two tablespoons of vegetable oil in jar “1” on top of the colored water. Do you see mixing of the liquids? What happens to the oil? Does it float on top or sink to the bottom?
Now take empty jar 2 and add the same liquids—but in reverse order. Start by pouring in two tablespoons of vegetable oil.
Is There Anybody Willing To Help Me With Physics And Chemisty Assignments. I AM WILLING TO PAY!!! Im Failing Majorly Bad & Really Need Help. Is There Anything Somebody Can Help I Have Cashapp, Paypal, Or Vemno. Please Drop Your Number Or Insta Or Anything That We Could Communitcate On.
What kinds of paintings did Winslow Homer make
Which group on the periodic table ways to lose electrons?
Answer:
Elements that are metals tend to lose electrons and become positively charged ions called cations. Elements that are nonmetals tend to gain electrons and become negatively charged ions called anions. Metals that are located in column 1A of the periodic table form ions by losing one electron.
Explanation:
hope it helps!