There are many important laws and theories in science. Which of the following is a law of scienco?
A living thing is made of at least one cell.
An atom is made of electrons orbiting a nucleus.
Gravity will pull two objects toward each other.
Natural selection will change species to fit their environments.

Answers

Answer 1

Answer: Gravity will pull two objects together.

Explanation: It’s newton’s 1 and kinda his 2 law.


Related Questions

Is caffeine additive?
Explain

Answers

Answer:yes anything can be addictive

Explanation:

Answer:

While caffeine produces a small rise in dopamine, it does not cause the large surge that unbalances the reward circuits in the brain and is necessary for an addiction. So even though the word “addiction” is often used casually, caffeine is not addictive (scientifically speaking).

An atom has 81 electrons, 84 neutrons, and 82 protons. What element is this atom?

Answers

Answer:

Lead

Explanation:

The subatomic particles within an atom can be used to know the atom or element given.

Of particular interest is the number of protons within the atom.

The periodic table is based on the atomic number of atoms. This atomic number is the number of protons within an atomic space.

So; If we know the number of protons within an atom, we can know the element.

The number of protons given is 82, the element is  therefore lead.

Answer:

The atomic number of polonium is 84. The atomic number lead is 82.

Explanation:

Many compressed gases come in large, heavy metal cylinders that are so bevy that they need a special cart to move them around. An 80.0-L tank of nitrogen gas pressurized to 172 arm atm is left in the sun and heats from its normal temperature of 20.0 degrees Celsius to 140.0 degrees Celsius. Determine (a) the final pressure inside the tank and (b) the work, heat, and delta U of the process. assume that behavior is ideal and the heat capacity of diatomic nitrogen is 21.0 j/molk.

Answers

Answer:

a) final pressure inside the tank is 242.4 atm

b)

Work = 0

heat q = 1440.85 kJ

DU = 1440.85 kJ

Explanation:

Given that;

Pressure P1 = 172 atm

Volume V = 80 L

Temperature T1 = 20°C = ( 273.15 + 20) = 293.15 K

Temperature T2 = 140°C = ( 273.15 + 140) = 413.15 K

we know that, gas constant R = 0.0821 atm.L/mol.K

from the Ideal Gas equation;

pV = nRT1

n = pV/RT1

we substitute

n = (172 × 80) / (0.0821 × 293.15)

n = 13760 / 24.067615  

n = 571.72 moles

now

P2 = nRT2/V2

P2 = (571.72 × 0.0821 × 413.15) / 80

P2 = 19392.5222 / 80

P2 = 242.4 atm

Therefore, final pressure inside the tank is 242.4 atm

b)

we know

w = -∫[tex]P_{ext}[/tex] dv

now, since there is no change in volume; dv = 0

so

w = 0

Work = 0

dU = cVDT

Cv = nCr,m

Cv = 571.72 ×  21.0

Cv = 12007.12 J/k

DU = CvΔT

DU = 12007.12 × (413.15 - 293.15)

DU = 1440854.4 J

DU = 1440.85 kJ

DU = q + w

1440.85 = q + 0

heat q = 1440.85 kJ

In Part III, the methyl orange indicator is used to monitor the equilibrium shifts of the acetic acid/acetate ion system. The methyl orange equilibrium established with water is Hmo(aq)(orange-red) H2O(l) H3O (aq) mo-(aq)(yellow). You compared the color of the solutions in three test tubes that initially contained 3 mL of 0.1 M acetic acid and a few drops of methyl orange indicator. In the first test tube, you added 1.0 M NaC2H3O2 drop wise. What color change was observed and what did this color change indicate about the shift in the methyl orange equilibrium

Answers

Answer:

See explanation

Explanation:

Let us look at the situation closely, the undissociated Hmo is red in colour while the mo^- is yellow in colour.

This means that an acidic solution will appear red while a basic solution will appear yellow in colour.

NaC2H3O2 is a basic salt. When it is introduced, the acetate ion pulls a proton from water forming  CH3COOH. CH3COOH is a weak acid and largely does not dissociate, it means that the undissociated acid remains in the solution leaving only the OH^- ions floating around thereby making the solution basic.

The colour of the system now changes to yellow.

Consider the equilibrium;

CH3COO^-(aq) + H2O(l) ------> CH3COOH(aq) + OH^-

Addition of NaC2H3O2  causes the equilibrium of this system to shift to the right.

The methyl orange water equilibrium also shifts towards the position where more mo^-(yellow) is produced.

According to the Michaelis-Menten equation, when an enzyme is combined with a substrate of concentration s (in millimolars), the reaction rate (in micromolars/min) is

Answers

Answer:

The answer is "A"

Explanation:

Please find the complete question in the attachment file.

[tex]\to R(s)= \frac{As}{K+s}[/tex]

when the s in the approach, that is infinity R(s) tends

[tex]\to \frac{A}{\frac{K}{s}+1} \\\\ \to\frac{A}{0+1} \\\\ \to\frac{A}{1} \\\\ \to A[/tex]

2. Each cart below is pushed across a room with the same amount of force. Which cart will result in the greatest change in speed?

A )A 15 kg cart being pushed with a 200 N force
B ) A25 kg box being pushed with a 200 N force
C )A 45 kg cart being pushed with a 200 N force
D )A 35 kg box being pushed with a 200 N force​

Answers

Answer: A 15 kg cart being pushed with a 200 N force.

Explanation:

The 15 kg cart is the lightest, so it has the least amount of friction on the ground.

The cart that will result in the greatest change in speed is the cart with a mass of 15 Kg

The correct answer to the question is Option (A) A 15 kg cart being pushed with a 200 N force

Acceleration is defined as the change in velocity of an object with time.

Acceleration is also related to force and mass according to the following equation:

Acceleration (a) = Force (F) / mass (m)

a = F / m

To answer the question given above, we shall determine the acceleration of the cart in each option.

For Option A:

Mass (m) = 15 Kg

Force (F) = 200 N

Acceleration (a) =?

a = F / m

a = 200 / 15

a = 13.33 m/s²

For Option B:

Mass (m) = 25 Kg

Force (F) = 200 N

Acceleration (a) =?

a = F / m

a = 200 / 25

a = 8 m/s²

For Option C:

Mass (m) = 45 Kg

Force (F) = 200 N

Acceleration (a) =?

a = F / m

a = 200 / 45

a = 4.44 m/s²

For Option D:

Mass (m) = 35 Kg

Force (F) = 200 N

Acceleration (a) =?

a = F / m

a = 200 / 35

a = 5.51 m/s²

From the illustrations made above, we can see that the cart with a mass of 15 Kg has the greatest acceleration (i.e change in speed)

Therefore, the correct answer to the question is Option (A) A 15 kg cart being pushed with a 200 N force

Learn more: https://brainly.com/question/25816322


What is the iupac name of ch3ch(oh)so3na

Answers

Answer:

propane-1-ol.

is the ans.

ok

is the name

ok

How do I know I'm a fish eh sorry

differences between selenium tellurium and polonium

Answers

Explanation:

Selenium and tellurium are rare elements, respectively, in order of crustal abundance. However, polonium, on account of its radioactive decay, is less abundant. The main source of selenium and tellurium is the anode slime deposited during the electrolytic refining of copper.

Energy from the Sun reaches Earth through
Convection
O radiation
conduction
all the above

Answers

Solar Radiation(Basically Radiation)

Solar radiation is the answer

Answer the given question: use Chapter 1 of notebook
How many formula units are there in 3.20x 102 moles of LICI? (2pts.)
Conversion factor: 1 mole LICI=
_formula of LICI
Students, draw anywhere on this slide!

Answers

Answer:

1.93 x 10²⁶ formula units

Explanation:

Given parameters:

Number of moles of LiCl  = 3.2 x 10² moles  = 320moles

Unknown:

Number of formula units in this compound  = ?

Solution:

The mole is used a reference to determine the number of substances matters contain.

 A mole contains the Avogadro's number of particles.

 So;

       1 mole of a substance contains 6.02 x 10²³ formula units;

320 moles of LiCl will contain 320 x  6.02 x 10²³  = 1.93 x 10²⁶ formula units

What are the correct products for the following reaction? ---->

K2SO4 + MgF2 ---->
Question 3 options:


2KF + MgSO4


F2SO4 + K2Mg


No reaction will occur


K2SO4 + F2Mg

Answers

Answer:

2KF+MgSO4

Explanation:

The correct product of the reaction above is 2KF + MgSO4.

What is a chemical reaction?

A chemical reaction is a reaction in which the reactants or reacting substances react or combine together to produce the products.

Therefore, The correct product of the reaction above is 2KF + MgSO4.

Learn more about chemical reactions below.

https://brainly.com/question/11231920

#SPJ2

15.0 g of Fe and 25.0 g of sand are added to 250.0 g of water. a. Determine the percent mass of Fe, sand, and water in the mixture. b. Create a flow chart illustrating how you could separate each of the mixture’s components. c. Explain which step of the separation is likely to have the highest amount of error.

Answers

Answer:

A. percentage mass of iron = 5.17%

percentage mass of sand  = 8.62%

percentage mass of water = 86.205%

B. (Iron + sand + water) -------> ( iron + sand) ------> sand

C. The step of separation of iron and sand

Explanation:

A. Percentage mass of the mixtures:

Total mass of mixture = (15.0 + 25.0 + 250.0) g =290.0 g

percentage mass of iron = 15/290 * 100% = 5.17%

percentage mass of sand = 25/290 * 100% = 8.62%

percentage mass of water = 250/290 * 100% = 86.205%

B. Flow chart of separation procedure

(Iron + sand + water) -------> separation by filtration using filter paper and funnel to remove water --------> ( iron + sand) -----------> separation using magnet to remove iron ------> sand

C. The step of separation of iron and sand by magnetization of iron will have the highest amount of error because during the process, some iron particles may not readily be attracted to the magnet as they may have become interlaced in-between sand grains. Also, some sand particle may also be attracted to the magnet as they are are borne on iron particles.

Use what you have learned to match the parts of the
Someone help!!!!FAST
sentences.
The mantle
is both solid and molten.
The core
is the outermost layer.
The part that includes land and water
is called the crust.
The crust
is under the crust.

Answers

Answer:

the crust is the outermost layer

Explanation:

the mantle is under the crust, the core is the innermost layer

land and water.is for crust-mantle. contain semi-molten iron and nickel please make the question clear

Answer:

answer in picture

Explanation:

calculate the number of atoms in 0.25 mole of uranium.

Answers

Answer: 0.25 mol × (6.02214 × 1023 /mol) = 1.5 × 10

Explanation: Hope that helps

Sally does the work in 2.3 hours and Pete does 2.5

Answers

pete because 2.5 x 2.3 is faster
I agree with the other comment

An ionic compound has a generic formula of QR2.

Which elements could the Q and R represent?

Once you choose an answer, check it by plugging those elements into the QR2 formula to see if it looks right.

Q= Sodium R= Oxygen

Q= Magnesium R= Chlorine

Q= Oxygen R= Sodium

Q= Chlorine R= Magnesium

Answers

Answer:

Q= Magnesium R= Chlorine

Explanation:

The element Q should be magnesium and R is chlorine.

An ionic compound is a compound that is formed by the combination of a metal and non-metal. Such bonds forms when there is a transfer of electrons from the metals to the non-metals. This leaves a net positive charge on the metal and a negative charge on the non-metal.

The electrostatic attraction leads to the formation of the bond.

 To solve this problem, the hypothetical compound is QR₂

       Mg                        Cl

     2 8 2                    2 8 7

So, Mg transfers 2 electrons to two atoms of chlorine.

 This leads to the formation of the compound MgCl₂

Heat is most closely related to which kind of energy?

Answers

Answer:

radial energy because it's a heat energy!

Explanation:

There are more types but that's the closest in my opinion!!

¿•¿

Thermal Energy

Explanation:

known as heat energy produced when a rise in temperature causes atoms and molecules to move faster and collide with each other.

Explain what would happen to the air temperature at Riverdale School over the course of the

day if the groundwater system were used.

Answers

Answer:

Air temperature increases.

Explanation:

The air temperature at Riverdale School increases if the groundwater system were used because this system uses very huge amount of water than the other system. By using more molecules having the same temperature, the thing with more molecules has more total kinetic energy or thermal energy than the thing with fewer molecules so that's why air temperature of the school is increases.

Why do organisms eat food? Be sure to explain your answer. ​

Answers

Answer:

Organisms need to take food to get energy and perform life processes. A living organism undergoes many life processes like nutrition, respiration, digestion, transportation, excretion, circulation of blood, and reproduction. To perform all these life processes the organism needs energy and nutrients.

Explanation:

nnastarannnn his idea

1. How many molecular orbitals can be built from the valence shell orbitals in O2?

Answers

Answer:

Atomic oxygen has 6 valence electrons and 4 valence orbitals (2s, 2px, 2py, and 2pz). We can draw a Lewis structure of molecular oxygen with a double bond between the oxygen atoms and 2 non-bonding pairs of electrons on each atom.

Given the equation:

4Al2O3 + 9Fe --> 3Fe3O4 + 8Al

If 27.5 g of Al2O3 reacted with 8.4 g of Fe, how many of Fe 3O4 are formed?

a) Calculate the limiting reactant


b) Calculate the number of grams of Al produced.


c) Calculate the number of grams of Fe3O4 produced.


d) Calculate the percent yield if 10g of Fe O4 were obtained?

Answers

Answer: a)  [tex]Fe[/tex] is the limiting reagent

b) 3.59 g

c) 11.6g

Explanation:

[tex]4Al_2O_3+9Fe\rightarrow 3Fe_3O_4+8Al[/tex]  

To calculate the moles :

   

[tex]\text{Moles of} Al_2O_3=\frac{27.5g}{102g/mol}=0.27moles[/tex]

[tex]\text{Moles of} Fe=\frac{8.4g}{56g/mol}=0.15moles[/tex]

According to stoichiometry :

a) 9 moles of [tex]Fe[/tex]  require= 4 moles of [tex]Al_2O_3[/tex]

Thus 0.15 moles of [tex]Fe[/tex] will require=[tex]\frac{4}{9}\times 0.15=0.067moles[/tex]  of [tex]Al[/tex]

Thus [tex]Fe[/tex] is the limiting reagent as it limits the formation of product and [tex]Al[/tex] is the excess reagent.

b) As 9 moles of [tex]Fe[/tex] give = 8 moles of [tex]Al[/tex]

Thus 0.15 moles of [tex]Fe[/tex] give =[tex]\frac{8}{9}\times 0.15=0.133moles[/tex]  of [tex]Al[/tex]

Mass of [tex]Al=moles\times {\text {Molar mass}}=0.133moles\times 27g/mol=3.59g[/tex]

c) As 9 moles of [tex]Fe[/tex] give = 3 moles of [tex]Fe_3O_4[/tex]

Thus 0.15 moles of [tex]Fe[/tex] give =[tex]\frac{3}{9}\times 0.15=0.05moles[/tex]  of [tex]Fe_3O_4[/tex]

Mass of [tex]Fe_3O_4=moles\times {\text {Molar mass}}=0..05moles\times 231.5g/mol=11.6g[/tex]

How many moles of water can be formed from 0.57 moles of hydrogen gas?

Answers

Answer:

0.57 water

Explanation:

To solve this problem, we need to write the reaction expression first.

The reactants are oxygen gas and hydrogen gas.

They react to give a product of water

       2H₂    +    O₂   →   2 H₂O  

Given that;

Number of moles of hydrogen gas = 0.57moles

From the balanced reaction expression;

       2 moles of hydrogen gas produces 2 moles of water

   So;

    0.57mole of hydrogen gas will also produce 0.57 water

Question 6 / 20
Which statement is always true about conservation of matter?
A. The mass of a system does not change during a chemical reaction
B. If a solid forms, the mass of a system increases
C. If a gas forms, the mass of a system decreases
D. The mass of a system changes when a substance changes from liquid to gas, but it does not change in
a chemical reaction
Select an answer
Back
Open notes navigator

Answers

Answer:

i gussss D is the answer may be

Answer:

A. The mass of a system does not change during a chemical reaction

Explanation:

Correct Answer

what divided by 700000 equals 4

Answers

I think it’s 280000

GRADE 5 SCIENCE MYA-2020-2021
Testosters are testing the choict of light on a radiometer Team 1 finds that blue light makes the radiometer spin slower when a blue light is 35 centimeters (cm) away. To validate Team 1's test results, how must
Text with and that is 20 cm away
Test what that is 45 cm away
Test with a green light that is 40 cm away
Test with the light that is 35 cm away

Answers

Answer:

Test it with a blue light that is 45 cm away.

Explanation:

Suppose that you are given a mixture of proteins with their properties provided in the following chart.
Isoelectric point PI Molecular weight
Protein A 4.1 80
Protein B 9.0 81
Protein C 8.8 37
Protein D 3.9 172
Choose one combination of techniques that can be used to isolate Protein B from Proteins A, C, and D.
a. gel filtration chromatography and ultracentrifugation
b. dialysis and ultracentrifugation
c. dialysis and ion exchange chromatography
d. ion exchange chromatography and gel filtration chromatography

Answers

Answer:

The correct option is d. ion exchange chromatography and gel filtration chromatography

Explanation:

The mixture contains proteins with different isoelectric points and molecular weights. Ion exchange chromatography separates the proteins with different electric charges, which depend on the isoelectric point. At certain pH of the aqueous medium, the proteins will have a certain electric charge and they will be retained differently in the stationary phase. Proteins A and D have similar isoelectric points (around 4.0) and maybe they cannot be efficiently separated by this method; the same occurs with protein B and C (with an isoelectric point around 9.0). To separate proteins A from D and protein B from C, it could be used gel filtration chromatography. This separation method is based on differences in molecular weights. So, at the end of the process, we will obtain the proteins A, B, C, D separated one from each other.

Conduction happens as energy flows from a warmer object to a cooler object. Which of the following is evidence of conduction?

Answers

Explanation:

Conduction is a form of heat transfer between one body and another. It usually occurs when a warmer object is in contact with a cooler one. Heat generally flows from a region of high temperature to a place at a lower temperature.

Conduction is very pronounced in solid bodies. The heat transfer causes a net transfer of the average kinetic energy of one body to the other. Some examples are: heating of iron by a hotter metallic body, the pot hand getting hotter as cooking continues, cooling of ice by touching it.

What is the value of 4.698 after rounding it down to 3 significant figures?

Answers

The value of 4.698 rounded down to 3 S.F is 4.70

What is aspartame? EXPLAIN

Answers

Answer:

it's an artificial non-saccharide sweetener 200 times sweeter than sucrose, and is commonly used as a sugar substitute in foods and beverages. it's a methyl ester of the aspartic acid/phenylalanine dipeptide with the trade names NutraSweet, Equal, and Canderel

Explanation:

Answer:

Aspartame is some type of very sweet substance that is used as an artificial sweetener, and chiefly in low-calorie products. It is a derivative of aspartic acid and phenylalanine.

Explanation:

water is a unique material in that the density of the solid is lower than the density of the liquid (which is why ice forms at the top of a pond and why ice floats in our drinks). if the density for ice at 0C is .917g/mL and the density for water at 0C is .999 g/mL, what is the calculated free space (as %) for each of these materials. you will need to estimate the volume of water as the sum of 2 H atoms and 1 O atom with radii 37 and 66 pm respectively. note that you will also have to assume a quantity of water to perform this exercise

Answers

Answer:

% Free space in water = [tex]\frac{9.945* 10^{-7} }{1*10^{-6} }[/tex]×100 = 99.45%

% Free space in ice  = [tex]\frac{9.98* 10^{-7} }{1*10^{-6} }[/tex]×100 = 99.8%

Explanation:

As given ,

Density for ice at 0⁰C = 0.917 g/ml

Density for water at 0⁰C = 0.999 g/ml

Radii of H atoms = 37 pm

Radii of O atoms = 66 pm

Now,

Consider 1 ml of water = 1 cm²

As , we know that mass of water in 1 cm² = 0.999 g

Moles of water = [tex]\frac{0.999}{18} = 0.056[/tex]

Volume of H₂O = 1.624×[tex]10^{-31}[/tex] m²

Now,

Volume occupied by water = 0.056×6.022×[tex]10^{23}[/tex]× 1.624×[tex]10^{-31}[/tex] m²

                                              = 5.48×[tex]10^{-9}[/tex] m²

⇒Volume occupied by water = 5.48×[tex]10^{-9}[/tex] m²

Now,

Free space = 1×[tex]10^{-6}[/tex]  - 5.48×[tex]10^{-9}[/tex] = 9.95×[tex]10^{-7}[/tex] m²

% Free space = [tex]\frac{9.945* 10^{-7} }{1*10^{-6} }[/tex]×100 = 99.45%

Now,

Consider 1 ml of ice  = 1 cm²

S.I unit of ice = 1×[tex]10^{-6}[/tex] m²

As , we know that mass of water in 1×[tex]10^{-6}[/tex] m² = 0.917 g

Moles of ice = [tex]\frac{0.917}{18} = 0.012[/tex]

Volume of H₂O = 6.022×[tex]10^{23}[/tex] ×0.012

Volume of ice unit = [tex]\frac{4}{3} \pi (37*10^{-12})^{3} *2 + \frac{4}{3} \pi (66*10^{-12})^{3} = 1.624*10^{-31}m^{3}[/tex]

Now,

Volume occupied by water = 0.012×6.022×[tex]10^{23}[/tex]× 1.624×[tex]10^{-31}[/tex] m²

                                              = 1.17×[tex]10^{-9}[/tex] m²

⇒Volume occupied by water = 1.17×[tex]10^{-9}[/tex] m²

Now,

Free space = 1×[tex]10^{-6}[/tex]  - 1.17×[tex]10^{-9}[/tex] = 9.98×[tex]10^{-7}[/tex] m²

% Free space = [tex]\frac{9.98* 10^{-7} }{1*10^{-6} }[/tex]×100 = 99.8%

Other Questions
5. What gametes are produced by the following organisms: a. Genotype YyRr, if Y and R are on different chromosomes b. Genotype YyRr, if dominant Y and R are on the same chromosome, no crossing over c. Genotype YyRr, if dominant Y and recessive r are on the same chromosome, no crossing over d. Genotype YyRr, if dominant Y and R are on the same chromosome, 50% crossing over When a researcher wishes to know how a set of participants changed over time or across repeated measures of a construct, the method that is conducted is: Which detail from "Go, John Glenn!" best explains how long it takes Friendship 7 to completely circle the earth? "With each hour-and-a-half orbit of Earth, Glenn watched the sun rise and set." "Five hours and 81,000 miles after he had taken off, John Glenn splashed down to a welcome." "For almost four hours he waited, on his back, his feet pushed up in front of him." "For twenty minutes, the capsule bucked and lunged while the temperature around it climbed." Joanna is a Master Sergeant in the U.S. Air Force. In June of 2019, her duty station changed from Offutt Air Force Base in Nebraska to Lackland Air Force Base in Texas. She drove 918 miles and spent $1,300 to move her household items. Joanna also incurred costs of $880 when she sold her home in her former city. Included on her Form W-2, in box 12, is code P for $1,484. Joanna's moving expenses adjustment is What is the answer to this question? Helppppp meeA.30 square unitsB.40 square units C.150 square units D.160 square units An atom of hydrogen consists of onesurrounded by oneproton, neutronneutren, pratenpreten, electronneutron, electron Which expression is equivalent to 3k + 5l + 6l + 2k?A) 8k + 8lB) 5k + 11lC) 5kD) 16 Find the value of x.64100XE Which character is the best example of a tragic hero brainly On what grounds did some people oppose Hamilton's plans? please math question lol asap Why did literacy rates rise the renaissance 14. Divided by 137.2 Is 6/2 simplified ? ............ What does an introduction do?a.reveals the main idea in a clear, easy-to-find mannerc.wraps up the text and restates the main ideab.Starts the text and catches the readers attentiond.none of the abovePlease select the best answer from the choices providedABCD Which of the following describes the developmental stages that infants experience? describe why people are better off not consuming an additional good or service if the marginal cost is greater than the marginal benefit. Two standard number cubes are tossed.What is the probability of getting a 5 onthe first number cube and an evennumber on the other? In a chemical change A. materials retain their properties. B. materials change their properties. C. new materials do not form. D. new materials formed are always in liquid form.