. Anthony proposed an experiment during which he would test the friction created when a skateboard is rolled along a flat surface. He selected three different surfaces (carpet, tile, and concrete) each with three different textures (dry, wet, and icy). His teacher told him that he would need to clarify his experiment before his project would be approved. Which of the following best describes why Anthony's project was rejected? A. Anthony's project has two independent variables. B. Anthony does not have a problem that can be tested. C. The skateboard will not be able to roll along the carpet. D. The friction created by a skateboard cannot be measured.​

Answers

Answer 1

Answer:D

Explanation:I think


Related Questions

Write the equation for the reaction of carbonic acid with hydroxide to produce hydrogen carbonate and water

Answers

Answer:

HCO3− + OH− ⇌ CO32− + H2O (fast)

Between pH values of 8 and 10, all the above equilibrium reactions are significant

You are going to standardize your sodium hydroxide by titrating with potassium hydrogen phthalate. As an example, you dissolve 0.3365 g of potassium hydrogen phthalate, otherwise known as KHP (KHC8H4O4) in water in a 250.0 mL Erlenmeyer flask and then add phenolphthalein indicator. You then titrate with your sodium hydroxide solution, which is in a buret, and you determine that the equivalence point is at 12.44 mL of your sodium hydroxide solution. Determine the molarity of your sodium hydroxide solution. What color will the solution of potassium hydrogen phthalate turn to determine when the equivalence point has been reached

Answers

Answer:

0.13 M

Explanation:

The reaction equation is;

NaOH(aq) + KHC8H4O4(aq) ------> KNaC8H4O4(aq) + H2O(l)

Molar mass of KHP = 204.22 g/mol

Amount of KHP= mass/ molar mass = 0.3365 g/204.22 g/mol = 1.65 × 10^-3 moles

n= CV

Where;

C= concentration

V= volume in dm^3

n= number of moles

C= n/V = 1.65 × 10^-3 moles × 1000/250 = 6.6 × 10^-3 M

If 1 mole of KHP reacts with 1 mole of NaOH

1.65 × 10^-3 moles of KHP will react with 1.65 × 10^-3 moles of NaOH

From

n= CV

We have that only 12.44 ml of NaOH reacted

C= n/V = 1.65 × 10^-3 moles × 1000/12.44

C= 0.13 M

At the equivalence point, the KHP solution turned light pink.

A 35.3g of element m is reacted with nitrogen to produce 43.5g of Compound M3N2, What is the molar mass of the element and the name of the element​

Answers

Answer:

The molar mass of an element is the mass in grams of one mole (6.02 x 1023 particles) of the element.

Hope it help

Explanation:

good luck

An ionic compound dissolves easily in water because
a.) the ionic lattice collapses.
b.) the ions changed their composition.
c.) the ions are separated by the water molecules in the solution.
d.) the ionic lattice becomes disordered. I

Answers

Answer:

I say.... C.

Explanation:

Ionic compounds dissolve in water if the energy given off when the ions interact with water molecules compensates for the energy needed to break the ionic bonds in the solid and the energy required to separate the water molecules so that the ions can be inserted into solution.

Hope it helps!~ (Sorry if you get it wrong or I got it wrong-)

~The Confuzzeled homan

The mass of a block is 12 g and the volume is 6 ml. Calculate the density of the block.

Question 2 options:

18 g/ml


72 g/ml


0.5 g/ml


2 g/ml

Answers

Answer:

According to mass and volume,  block density is 2 g/ml

Explanation:

Density is a measure, usually used in physics and chemistry, that relates the mass and volume of a solid or compound.

In general terms, the density is directly proportional to the mass, and inversely proportional to the volume, so increasing the mass will also increase the density.

The formula used to calculate the density is

ρ = [tex]\frac{m}{V}[/tex]

Therefore, according to the mass and density of the block

ρ = [tex]\frac{12}{6}[/tex] = 2g/ml

Being the density of the block equal to 2 g/ml.

The other options are not possible, because the values given do not correspond to the result of the equation.

What is the name of the cycle in which plants turn carbon dioxide into oxygen that animals can breathe

A. Water Cycle
B. Nitrogen cycle
C. Carbon dioxide-oxygen cycle
D. Rock cycle

Answers

Answer:

c

Explanation:

carbon dioxide oxygen cycle is basically photosinthesis

photosinthecis is where carbon dioxiode is turned to oxygen

The answer is C. By using the energy of sunlight, plants and convert carbon dioxide and water into carbohydrates and oxygen in a process

Predict the precipitate produced by mixing an Al(NO3)3 solution with a KOH solution. Write the net ionic equation for the reaction.

Molecular equation:


Complete Ionic Equation:

Net Ionic Equation:

Identify spectator ions:

Answers

Based on the reactants and products,

The molecular equation of the reaction is: Al(NO3)3 + 3 KOH ---> Al(OH)3 + NaNO3 The complete ionic equation of the reaction is: Al3+ 3NO3- + 3 K+ 3OH- ---> Al(OH)3(s) + 3 Na+ 3 NO3+The net ionic equation of the reaction is:Al3+ 3OH- ---> Al(OH)3(s) The spectator ions are: Na+ and NO3+

What is a precipitate?

A precipitate is a solid product formed in when two solutions of salts react by double replacement.

The molecular equation of the reaction of Al(NO3)3 solution with a KOH solution is:

Al(NO3)3 + 3 KOH ---> Al(OH)3 + NaNO3

The complete ionic equation of the reaction of Al(NO3)3 solution with a KOH solution is:

Al3+ 3NO3- + 3 K+ 3OH- ---> Al(OH)3(s) + 3 Na+ 3 NO3+

The net ionic equation of the reaction of Al(NO3)3 solution with a KOH solution is:

Al3+ 3OH- ---> Al(OH)3(s)

The spectator ions are: Na+ and NO3+

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how many protons does the bohr model have for helium?

Answers

Answer:

2 protons per atom of Helium

Explanation:

The number of proton in a given element is given by its place on the periodic table which is for He 2 protons b/c the atomic number for He is 2.

Other Examples:

Hydrogen (H-1) or Protium has 1 proton b/c its atomic number is 1.

Magnesium (Mg-24) has 24 protons  b/c  its atomic number is 24.

Lead (Pb-207) has 82 protons b/c its atomic number is 82.

Uranium (U-238) has 92 protons b/c its atomic number is 92.

The periodic table order of arrangement of elements is based upon 'The Periodic Law'. => The chemical and physical properties of the elements is a periodic function of atomic numbers, or number of protons in the nucleus.

BALANCING EQUATION
O XCiz(aq) +
O AgNO3(aq)
X(NO3)2(aq) + O Agci(s)
DONE
7:05 PROGRESS: 14%
XE
equation on the wall display.
WE button when you think you

Answers

Answer:

i think it would be

Explanation:

What is the unit rate of the better deal? (Number answers only.)

LaTeX: \frac{160\:miles}{5\:gallons}\:or\:\frac{315\:miles}{9\:gallons}160 m i l e s 5 g a l l o n s o r 315 m i l e s 9 g a l l o n s

The better deal has a unit rate of [m] miles per gallon.

Dinitrogen oxide has _____.

Answers

Answer:

Nitrogen is the answer my good sir.

Explanation:

Solve the following, Report your answer with correct number of significant figures
23.27-72.058
0.0853+0.05477+0.0002
35/0.0622
3400*0.00800
(43.1+27.250)*(22.514-18.0)​

Answers

The solution for the arithmetic problems are​ is mathematically given as

23.27-72.058=-48.79

0.0853+0.05477+0.0002=0.14

35/0.0622=562.7

3400*0.00800=27.2

(43.1+27.250)*(22.514-18.0)​=317.56

What is the solution for the arithmetic problems?

Question Parameter(s):

23.27-72.058

0.0853+0.05477+0.0002

35/0.0622

3400*0.00800

(43.1+27.250)*(22.514-18.0)​

Generally,

23.27-72.058=-48.79

0.0853+0.05477+0.0002=0.14

35/0.0622=562.7

3400*0.00800=27.2

(43.1+27.250)*(22.514-18.0)​=317.56

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Please calculate your BMI by taking your mass in kilograms divided by your
height in meters squared. Please help me out

Answers

Answer:

you find your bmi by dividing your weight in kg by your height in Meters then square it

this is the formula kg/m2

Explanation:

7. Which of the following medications should most likely not be taken prior to
operating heavy machinery?
a. Penicillin (antibiotic)
b. Famotidine (stomach)
C. Diphenhydramine (Benadryl)
d. Hydrochlorothiazide (diuretic)

Answers

Diphenhydramine medications should be taken by person who operate heavy machinery.

What is Medications?

Medications refers to drugs or substances taken into the body to relieve of pains or symptoms of diseases.

What is Diphenhydramine?

Diphenhydramine is also called Benadryl and is antihistamine take to relieve symptoms of pains, allergy, hay fever, and the common cold symptoms like cough, sneezing, sore throat, cold , cattarh and so on. It is used to treat dizziness, nausea, vomiting and motion sickness. Diphenhydramine can be taken to relax the body and fall asleep.

Therefore, Diphenhydramine medications should be taken by person who operate heavy machinery because it will help relive pains and symptoms of cold which can be due to vigorous activity of operating heavy machinery.

Learn more about Diphenhydramine from the link below.

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Hydrogen gas and solid gold(III) sulfide are reacted. Pure solid gold metal is formed and gaseous hydrogen sulfide is released. Correctly identify the reactants and products:reactants:

a. solid gold, gaseous hydrogen sulfideproducts: hydrogen gas, solid gold(III)
b. sulfidereactants: solid gold, solid gold(III) sulfideproducts: hydrogen gas, gaseous
c. hydrogen sulfidereactants: hydrogen gas, solid gold, gaseousproducts: hydrogen sulfide
d. solid gold(III) sulfidereactants: hydrogen gas, solid gold(III)
e. sulfide products: solid gold, gaseous hydrogen sulfide

Answers

The reactants of the reaction will be solid gold (III) sulfide and hydrogen gas, while the products will be pure solid gold and hydrogen sulfide gas.

Chemical reactions

Reactants react together during reactions to arrive at products.

In this case, solid gold (III) sulfide and hydrogen gas react according to the following equation:

[tex]Au_2S_3(s) + 3 H_2 (g)-- > 2 Au(s) + 3H_2S(g)[/tex]

Reactants = solid gold (III) sulfide, hydrogen gas

Products: pure solid gold, hydrogen sulfide gas

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Question 3 of 5
Which two characteristics describe the pair of objects experiencing greater
gravitational force?
2 kg
2 kg
S kg
5 kg
d = 1 m
d = 5 m
D A. More mass
B. Greater distance between them
C. Shorter distance between them
I D. Less mass
SUS

Answers

Answer:

A. More mass

C. Shorter distance between them

Explanation:

The two characteristics of a body experiencing greater gravitational force are that they have mass and a shorter distance between them.

This is conformity with Newton's law of universal gravitation.

The law states that "every object attracts one another with a force that is directly proportional to their masses and inversely proportional to the square of the distance between them".

This law implies that the more the mass of two bodies, the more the gravitational force of attraction. And that the shorter the square of the distance between them, the more the attraction.

Answer:

A. More Mass And

C. Shorter Distance Between Them

Explanation:

I Know This Is Already Answered But I'm Ok With It.

A UNKNOWN metal displaces alumiun from a solution but does not displace sodium. using actvity series, determine unknown metal

Answers

Explanation:

k

na→cannot displace

ca

mg

al→can displace

zn

fe

sn

pb

h

cu

hg

ag

pt

au

the answer is calcium or magnesium

because that metal's activity will be higher than al and

lower than Na. so that the metal will be ca or mg.

Calculate the volume of the gas, in liters, if 1.35 mol
has a pressure of 1.30 atm
at a temperature of -6 ∘C?

Answers

Answer:

22.8 L

Explanation:

Step 1: Given data

Moles of the gas (n): 1.35 molPressure of the gas (P): 1.30 atmTemperature (T): -6°CIdeal gas constant (R): 0.0821 atm.L/mol.K

Step 2: Convert "T" to Kelvin

We will use the following expression.

K = °C + 273.15 = -6 + 273.15 = 267 K

Step 3: Calculate the volume of the gas

We will use the ideal gas equation.

P × V = n × R × T

V = n × R × T / P

V = 1.35 mol × (0.0821 atm.L/mol.K) × 267 K / 1.30 atm

V = 22.8 L

Which has the greater density?

A) Air at 20 km altitude

B) Air at sea level​

Answers

Answer:

Air at sea level

Explanation:

sry If Im wrong

air at sea level
explanation: because it has the greater density.

Question 25 (2 points) ✓ Saved
Consider these three compounds.
I
II
H
III
H
1
H-C-H
H-C-H
ннннн
! ! ! ! !
H-Ċ-Ċ-Ċ-Ċ-Ċ-H
II 1
Η Η Η Η Η
H H
1
1
H-C-C-C-H
HHH
H HH
1
H-C-C-C-C-H
I 1
Η Η Η Η
Which are isomers?

Answers

Answer:

May be its correct bro

Explanation:

take it easy

How many grams are in 0.55 moles of C6H10S?

Answers

Answer:

62.7 gram

Explanation:

Molar mass = (6)(12)+(10)(1)+(1)(32)=114 g/mol

Mass = no of moles × molar mass

= 0.55 × 114 = 62.7 gram

The mass of 0.55 moles of compound C₆H₁₀S is equal to 62.7 g.

What is a mole?

A mole is defined as a standard unit that is used to find a huge number of quantities such as atoms, molecules, ions, or other particles. The mass of the 1 mole of any chemical element is equal to the atomic mass of the element and that of any chemical compound is known as molar mass.

The number of entities in 1 mole was found to be equal to 6.023 × 10²³ which is known as Avogadro’s number or Avogadro's constant

Given, the number of moles of the given compound = 0.55 moles

The mass of 1 mole of given compound C₆H₁₀S  = 114 g/mol

The mass of 0.350 moles of the given compound = 0.55 × 114 = 62.7 g

Therefore, 62.7 grams is the mass of 0.55 moles of C₆H₁₀S.

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#SPJ2

What is the equivalent mass of 2 moles of oxygen

Answers

Answer:

32 g

Explanation:

the molar mass of oxygen is 16 g

if it's asking o2 then 64

How many atoms are in 3.5 L of Neon at STP? Show your work!

Answers

Answer:

This is the answer to the question 0.1734

Explanation:

3.5/20.18

=0=1734

When 2.499 g of AX (s) dissolves in 135.3 g of water in a coffee-cup calorimeter the temperature rises from 23.6 °C to 35.2 °C. Calculate the enthalpy change (in kJ/mol) for the solution process. AX space (s )space rightwards arrow straight A to the power of plus (a q )space plus space straight X to the power of minus space (a q )Assumptions for this calculation: The specific heat of the solution is the same as that of pure water (4.18 J/gK) The density of water = 1.000 g/mL The liquid’s final volume is not changed by adding the solid The calorimeter loses only a negligible quantity of heat. The formula weight of AX = 59.1097 g/mol. Be sure you include the correct sign for the enthalpy change.

Answers

Answer:

The enthalpy change for the solution process [tex]\Delta H_{rxn}[/tex] = - 158.34 kJ/mol

Explanation:

Given that:

The mass of salt AX = 2.499 g

The mass of water = 135.3 g

The mass of the solution = ( 2.499 + 135.3 ) g = 137.799 g

The specific heat of salt solution s is known to be = 4.18 J/g° C

The change in temperature i.e. ΔT = 35.2 °C -  23.6 °C = 11.6 °C

Thus, the amount of heat raised is equal to the heat absorbed by the calorimeter.

[tex]q_{reaction} = q_{solution}[/tex]

[tex]q_{reaction} = -ms_{solution} \Delta T[/tex]

[tex]q_{reaction} = -137.799 \ g \times 4.18 \dfrac{J}{g^0C}\times 11.6^0C[/tex]

[tex]q_{reaction} = - 6682 \ J[/tex]

[tex]q_{reaction} = - 6.682 \ kJ[/tex]

Recall that the mass of the salt = 2.499 g

The number of moles of the salt = [tex]2.499 \ g \times \dfrac{1 \ mol \ of \ AX}{59.1097 \ g}[/tex]

= 0.0422 mol of AX

Finally the enthalpy change, [tex]\Delta H_{rxn} = \dfrac{- 6.682 \ kJ}{ 0.0422 \ mol}[/tex]

= - 158.34 kJ/mol

The enthalpy change for the solution process [tex]\Delta H_{rxn}[/tex] = - 158.34 kJ/mol

Copper, a metal known since ancient times, exists in two stable isotopic forms, 6329Cu (69.09%) and 6529Cu (30.91%). Their atomic masses are 62.93 amu and 64.9278 amu respectively. Calculate the average atomic mass of copper.

Answers

Answer:

Wt. Avg. Atomic Weight => 63.35457 amu

Explanation:

Given              Isotopic             %Abundance     fractional          Wt Avg

                  At. Mass (amu)                                  abundance      contribution                    

Cu-63              62.93                      69.09              0.6909            43.4783

Cu-65              64.9278                  20.0668        0.200668        20.0668

Wt Average of all isotopes = ∑Wt Avg Contributions

=  43.4783 amu + 20.0668 amu = 63.35457 amu

What trend does electronegativity follow, going down the periodic table?

Answers

electronegativity increase across a period and decreases down a group

Answer: Decreases

Explanation: Electronegativity decreases because the valence electrons are farther from the nucleus.

What is true about asteroids

Answers

Answer:

They are big rocks that fly through space and are made of most commonly chondrite. When they collide, they collide with such force that they create craters on places like the moon.

Answer the following questions about the mechanism for the acid-catalyzed hydration of an alkene:

a. How many transition states are there?
b. How many intermediates are there?
c. Which step in the forward direction has the smallest rate constant?

Answers

Answer:

a) there are three transition states

b) there are two intermediates; carbocation and protonated alcohol

c) The first step in the forward direction

Explanation:

The acid-catalysed hydration of alkenes proceeds via a carbocation mechanism.

Three transition states can be identified in this mechanism for the acid-catalyzed hydration of alkenes.

The three transition states are derived from the three steps in the reaction sequence:

1) Protonation of the alkene by hydronium ion

2) Addition of water to the carbocation

3) loss of a proton to yield the alcohol

The first step involves the breaking of a pi bond, hence it is a slow step hence it has the smallest rate constant. The other two steps are fast steps.

The colors of fireworks are produced by metals

Answers

Answer:

True

Explanation:

Answer:

Yes

Explanation:

They are produced by heating metal salts eg. Aluminium it is used to produce silver and white flames and sparks.

HOPE IT HELPED

Which two photos show electric force in action?
D A
O B.
OC
D D

Answers

Answer:

b and d show electric force in action

Explanation:

How many gallons of concentrated sulfuric acid (density of 1.84 g/cm3) are required to have a mass of 184.33 pounds?

Note: 1 kg = 2.204 lb, 1 gallon = 3.79 L.

Answers

After series of conversion from one unit to another, the number of gallons was found to be 12 litres

Density, Mass and Volume

Given Data

Density of Sulfuric acid = 1.84 g/cm3Mass of Sulfuric acid = 184.33 Pounds

Conversion from pounds to Gram

1 kg ---------2.204 lb

x kg ---------184.33 lb

x = 184.33/2.204

x = 83.634 kg

hence the mass in gram = 83.634*1000

mass in gram = 83634 g

Now let us find the volume

We know that density = mass/volume

volume = mass/density

volume = 83634/1.84

volume = 45453.26 cm^3

Convert cm^3 to litres

Volume in litres = 45453.26 /1000

Volume in litres = 45.45 Litres

Convert from Litres to Gallons

1 gallon = 3.79 L

x gallons =  45.45 L

x =  45.45/3.79

x gallons = 11.99 L


Approx = 12 Litres

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