Answer:
B. Controlled variables
Explanation:
The Dependent sample t-test compares the mean score of measurements in one group to that of another other group. It mainly used when analyzing comparable sample units as it pairs repeatable observations within a time frame.
Controlled variables are factors that are not tested and remain constant. Some examples of controlled variables are temperature, pressure, volume etc
Yo can someone help me answer this
Answer:
D
Explanation:
You need both, independant and dependant variables for a hypothesis.
What is the percent composition of nitrogen in N 2 O
Answer:
63.6%
Explanation:
The given compound is:
N₂O;
The problem here is to find the percent composition of nitrogen in the compound.
First find the molar mass of the compound:
Molar mass of N₂O = 2(14) + 16 = 44g/mol
So;
Percentage composition of Nitrogen = [tex]\frac{2 x 14}{44}[/tex] x 100 = 63.6%
What happens when the compound Mgo is formed? (5 points)
Oxygen transfers two electrons to magnesium.
Oxygen receives two electrons from magnesium.
Magnesium forms an ion with -1 charge; oxygen forms an ion with +1 charge.
Magnesium forms an ion with +1 charge; oxygen forms an ion with -1 charge.
Answer:
Oxygen receives two electrons from magnesium.
Explanation:
Hello!
In this case, considering the chemical reaction by which magnesium oxide is produced:
[tex]2Mg+O_2\rightarrow 2MgO[/tex]
In that case, if we show up the oxidation states, we have:
[tex]2Mg^0+O_2\rightarrow 2Mg^{2+}O^{2-}[/tex]
In such a way, since metals, like magnesium, have the capacity to lose electrons, rather than receive them, we infer why it turns out with +2 rather than -2; thus, we the correct answer is "oxygen receives two electrons from magnesium." because it results with -2 in MgO.
Best regards!
Answer:
Oxygen receives two electrons from magnesium.
Explanation:
What are the reactants in the reaction? What are their properties? Perform a quick Internet search, if needed.
The reactants in this reaction are sodium and chlorine. Sodium is a soft, silvery-white metal that is highly reactive. Chlorine is a poisonous greenish-yellow gas that has an odor and combines readily with other elements.
This might be the exact question so you might wanna rephrase it but good luck! :)))
A reactant is a substance that undergoes change during a chemical reaction.
A reaction in a chemical experiment is which takes place when there are mixtures between two or more reactants.
There are about four types of reactions which are:
SynthesisDecompositionSingle replacementDouble replacementPlease note that your question is not complete, therefore, i would give you a general overview to help you.
Some examples of reactants include:
HydrogenSodiumChlorine, etcRead more here:
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Thomas calculates the volume of an object by multiplying the measurements 1.74 cm x 2.3 cm x 3.09 cm. Using significant figures, how should the answer be reported?
Answer:
12 cm³
Explanation:
Always round to the place of the number with the least amount of significant figures.
1.74 and 3.09 have three significant figures. 2.3 has two significant figures. Therefore, the answer will be rounded to two significant figures.
1.74 cm × 2.3 cm × 3.09 cm = 12.36618 -> 12 cm³
(The 3 in the tenths place is less than 5 so drop it and all the numbers to the right of it.)
Hope that helps.
Bohr's model of the atom attempts to explain the idea that:
A) protons and neutrons are found in the nucleus
B) all atoms of one type of element are identical
C) energy is quantized
D) the atom is mostly empty space
It attempts to explain the idea that:C. energy is quantized
Balance the Chemical Equation
Pb(OH)2 + HCl ---> H2O + PbCl2
Please help
Answer:
Pb(OH)2 + 2 HCl ---> 2H2o + PbCl2
Explanation:
The chemical equation below shows the photosynthesis reaction.
6CO2 + 6H2O → C6H12O6 + 6O2
A reaction uses 528 g of CO2. How many grams of water are used in this reaction?
Answer:
12
Explanation:
Will get brainliest.
Answer:
1.00 g
Explanation:
got it on pex
a compound has hydrogen ion and nitrate ion in solutionstate what is the name of that compound
Answer:
This compound is HNO2
Explanation:
HNO2 ----> H+ + NO2
When metals and non metals combine in fixed proportion then a chemical compound is formed So, the compound that will be formed from hydrogen ion and nitrate ion is Hydrogen nitrate.
What is chemical formula?
Chemical formula is a formula where cation and anion combine to form a molecule in fixed proportion. Metals combine in form of cation and non metals combine in form of anion.
Cation is the species that give electron and attain positive charge while anion is a species which gain electron and attains negative charge so when anion and cation combine in fixed ration the the overall charge of the molecule is zero that is molecule is neutral, the charge over cation and anion is also called oxidation state.
Therefore, the compound that will be formed from hydrogen ion and nitrate ion is Hydrogen nitrate.
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What is the definition of momentum?
A- The amount of matter in an object.
B-Mass in motion.
C-Speed with direction.
D- The resistance to change motion
Answer:
B. Mass in motion. Is the definition of momentum
Item 17 Which symbol represents a salt? C2H2 C6H12O6 KCl O2 Item 17 Which symbol represents a salt? C2H2 C6H12O6 KCl O2
Answer:
The symbol that represent a salt is CaCl2
Explanation:
The CaCI2 is the calcium chloride that an organic compound now a salt having a chemical formula i.e. CaCI2. Also it is non-color cyrstalline solid at the room temperature also it is highly soluble in the water
Therefore as per the given situation the symbol that represent a salt is CaCI2
This is the answer and the same is not provided in the given options
Determine the empirical formula for a compound with 68.4% Cr and 31.6% O. Show your work in the space below.
Answer:
Cr2O3
Explanation:
To find the empirical formula, which is the smallest whole number ratio of a compound, the following is done:
68.4% Cr = 68.4g of Chromium
31.6% O = 31.6g of Oxygen
Since, Cr = 52, O = 16, divide each mass by their respective atomic mass to convert to moles.
Cr = 68.4/52 = 1.315 mol
O = 31.6/16 = 1.975 mol
- Next, we divide each mole value by the smallest value (1.315mol)
Cr = 1.315/1.315 = 1
O = 1.975/1.315 = 1.50
The ratio or Cr to O is 1:1.5
We multiply this ratio by 2 to get the whole number ratio as follows:
2 × 1: 2 × 1.5
2:3
Hence, the empirical formula of Cr and oxygen is Cr2O3.
How many carbon atoms are represented by the model below?
Answer:
3
Explanation:
Star A and star B are the same distance away from earth. From earth, star A seems brighter than star B. Which star has the highest absolute brightness?
Answer:
Star B
Explanation:
Star B, this is because, usually in the discussions about stars, the more luminous star or say, the brighter star usually is the one that possesses the smaller absolute brightness.
That being said, succinctly put, if we have two stars A and star B, if star A is brighter than star B, then star A has a lower absolute brightness. Also, if star B is less brighter than star A, then it has the higher absolute brightness.
Answer:
STAR B
Explanation:
Give the symbol for the element with the following orbital diagram:
↑↓
1s
0000
↑↓
2s
0000
↑↓
↑↓
2p
↑↓
0000
↑↓
3s
0000
↑↓
↑↓
3p
↑↓
0000
↑↓
4s
0000
↑↓
↑↓
↑↓
3d
↑↓
↑
The given orbital diagram are iron and symbol for the element is Fe
Orbital diagrams are a pictorial description of electrons in an atom and where electron go in atom then we have to follow three rules, and the first one being the Auf bau Principle, the Auf bau Principle states that each electron occupies the lowest energy orbital first filled and the second is pauli exclusion principle in which only two electron are present which is in opposite spin and third is hunds rule of maximum multiplicity in which pairing of electron is not possible until orbital are singly occupied this rules are used for filling the electron here given orbital diagram in which 1s²2s²2p⁶3s²3p⁶4s²3d⁶ means the element is iron and symbol of this element is Fe
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Write the following numbers in scientific notation: a) 0.0006730 b)50000.0 c)0.000003010 d) 132.40 e)2232
Answer:
a)6.730×10⁻⁴
b)5×10⁴
c)3.010×10⁻⁶
d)1.3240×10²
e)2.232×10³
The given numbers in scientific notation are [tex]6.730 \times 10^{-4}[/tex], [tex]5.0 \times 10^4[/tex], [tex]1.3240 \times 10^2[/tex], [tex]2.232 \times 10^3[/tex] and [tex]2.232 \times 10^3[/tex], respectively.
Scientific notation is a way of expressing very large or very small numbers in a compact and convenient form.
To express a number in scientific notation, we need to write the number in the form: [tex]\rm a\times 10^b[/tex]
a) 0.0006730 can be written in scientific notation as [tex]6.730 \times 10^{-4}[/tex]. The decimal point was moved 4 places to the right, so the exponent is negative 4.
b) 50000.0 can be written in scientific notation as [tex]5.0 \times 10^4[/tex]. The decimal point was moved 4 places to the left, so the exponent is positive 4.
c) 0.000003010 can be written in scientific notation as [tex]3.010 \times 10^{-6}[/tex]. The decimal point was moved 6 places to the right, so the exponent is negative 6.
d) 132.40 can be written in scientific notation as [tex]1.3240 \times 10^2[/tex]. The decimal point was moved 2 places to the left, so the exponent is positive 2.
e) 2232 can be written in scientific notation as [tex]2.232 \times 10^3[/tex]. The decimal point was moved 3 places to the left, so the exponent is positive 3.
Therefore, [tex]6.730 \times 10^{-4}[/tex], [tex]5.0 \times 10^4[/tex], [tex]1.3240 \times 10^2[/tex], [tex]2.232 \times 10^3[/tex] and [tex]2.232 \times 10^3[/tex], are the scientific notation for the given numbers.
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A 1,600-milliliter bucket of paint is at a temperature of 70°F. Then the paint is divided equally into four smaller buckets. Each bucket is at 70°F before the paint is poured.
the temperature of each 400 milliliter bucket is about _____ the temperature of the original bucket of paint.
a.the same as
b.four times
c.one fourth
science
Answer:
a.the same as
Explanation:
The temperature of each 400mL bucket is about the same as the temperature of the original bucket of paint.
This is because the temperature of the paint inside the bucket is not dependent on the amount of paint present.
In this regard, the temperature is an intensive property. So each of the boxes will have a temperature that is the same as that of the original bucket. Each of the particles have the same amount of kinetic energy.How can I determine basic oxide from peroxide by looking
What coefficient will balance the equation that is shown?
Al +_ HCI-H2 + ALCI,
Balanced equation :
2Al +6HCI⇒ 3H₂ + 2AlCI₃
Further explanationGiven
Reaction (unbalanced)
Al +HCI⇒ H₂ + ALCI₃
Required
Balanced equation
Solution
Give a coefficient
aAl +bHCI⇒ cH₂ + AlCI₃
Al, left = a, right=1⇒a= 1
Cl, left = b, right=3⇒b=3
H, left = b, right=2c⇒b=2c⇒3=2c⇒c=3/2
The equation becomes :
Al +3HCI⇒ 3/2H₂ + AlCI₃ x 2
2Al +6HCI⇒ 3H₂ + 2AlCI₃
84 pt =_____ qt
5.0 gal =_____ L
Answer:
84 pt =__50.4399___ qt
5.0 gal =___18.9271__ L
Explanation:
Have A Wonderful Day!!
Answer: 84 pints = 42 quarts
5.9 gallons = 1.89271
Explanation:
Why do you think the different heating process result in different softness or hardness of the steel? Think about what steel is made of and how the atoms move .
Explanation:
Different heating process affect the microstructure of the steel in different ways. Thus, imparting different properties to the steel. For example, annealing is done is done to impart softness to steel, hardening is done to hardened the steel( eg: carburizing, nitriding, cyaniding) whereas tempering is done to improve the ductility of the steel.
Steel mainly contains iron and carbon. This percentage of carbon and iron decides the property of the steel. It is the % of carbon which is altered in different heating process that to obtained the desire microstructure in steel.
PLZ HELP !!!!!
Which statement correctly describes the main difference between body waves and surface waves?
Select one:
Surface waves are only longitudinal waves and body waves are only transverse waves.
Surface waves only travel across oceans and body waves travel across the Earth’s crust.
Surface waves are less damaging to man-made structures than body waves.
Surface waves travel across the Earth’s surface and body waves travel through the Earth’s interior.
Surface waves travel across the Earth’s surface and body waves travel through the Earth’s interior.
there you go :)
for an electron to move from an energy level that was close to the nucleus to an energy level that is far from the nucleus would it need to gain or lose energy ?
Answer:
it would need to lose energy
Explanation:
I don't really have an explanation
As the electrons gets closer to the nucleus, by the electrostatic force of attraction electrons are tightly bound to the nucleus. To move the inner electron to outer shell, high energy have to applied to weaken the nuclear force.
What is nuclear force?Nuclear force is the force by which the nucleon are bind in the nucleus and electrons are attracted towards the nucleus. The positively charged protons inside the nucleus electrostatically attracts the negatively charged electrons.
The minimum amount of energy required to remove an electron from the valence shell by overcoming the nuclear force is called ionization energy.
To bring an electron which is closer to the nucleus to the outer shell needs much energy to reduce the nuclear attractive pull. The energy need to gain.
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Hellppppppppplplllppp
Answer:
the third one because oceans don't affect the weather
Explanation:
Write a chemical equation of Dr. Jeff's demonstration using a battery to light steel wool on fire. The battery is used to allow a current to travel through the steel wool, thus heating it. Steel wood is made from iron (Fe).
Answer:
2Fe(s) + 3O2(g) --------> 2FeO3(s)
Explanation:
According to the question, a battery was used to light the steel wool by bringing the terminals very close together. When the battery came into contact with the steel wool, current was sent out through the thin wire. This caused the iron to heat up quite well.
Iron reacts with oxygen under these conditions as follows;
2Fe(s) + 3O2(g) --------> 2FeO3(s)
This is the chemical reaction that occurs when the steel wool is set on fire.
Chemical equation involved in Dr. Jeff's demonstration is
2 Fe+3 O₂[tex]\rightarrow[/tex]2 FeO₃
What is the effect of heating in chemical reactions?Battery is a device which helps in conduction of current. When a battery is used to pass a current through a substance in this case which is steel wool made up of iron it starts getting heated up.
The amount by which substance gets heated up is directly proportional to the current passing through it. As more current is passed through the battery it gets heated more.
During heating, the iron present in the steel wool reacts with oxygen to form iron oxide with iron present in the+3 oxidation state.When the heat exceeds a certain point the steel wool catches fire due to the heat generated. The heat causes the electrons present in steel wool of iron to move faster and collide with each other thus generating more heat.
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The downward movement of water through pores and other spaces in soil due to gravity is called____
A Iniltration
B evaporation
C soakation
D seepage
Answer:
A Infiltration
Explanation:
The downward movement of water through pore spaces and other spaces in soil due to gravity is called infiltration.
Infiltration is greatly due to the force of gravity forcing water through pore spaces downward.
The ground water recharge is also impacted by this downward motion of water. In areas where the surface of the soil is covered with concrete, infiltration is not possible. Soil water content is due to the movement of water by infiltration.For work to be done on an object:
*
The work input must be equal to the work output
The energy input must be equal to the energy output
Only a force must be applied, moving the object is not required
The object has to move a distance when a force is applied to it
Answer:
The object has to move a distance when a force is applied to it
Explanation:
For work to be done on a body the force applied must move the body through a particular distance.
Work done = Force x distance
If no distance is moved by the force, no work is done.
Also, the angle between the force and the distance must be 0 to do the maximum work on the body.
Which element below would most likely gain 3 electrons?
Answer:
Lithium
Explanation:
Can compounds be broken down into the elements they are made of?
Answer:
yes, some can
Explanation:
because like salt an other compounds by being decomposed