Answer:
A
Explanation:
The correct answer would be that the group being given the sugar pill is being used as the control group.
In a typical experimental study, there are two groups of subjects:
1. The treatment or the experimental group
2. The control group
The treatment group receives the treatment variable while the control group does not receive or is given a placebo. Thus, the control group act as the reference group for comparison basis. Any difference in the observation between the two groups would be attributed to the treatment variable.
The correct option is, therefore, A.
PLEASE ANSWER QUICKLYYY
At standard temperature and pressure one mole of H2 gas occupies
22.4 L. What is the volume occupied by 3.50 moles of H2?
Answer 78.4
Explanation:
Idfk calculations
A mixture of four gases exerts a total pressure of 960
mm Hg. Gase A each exert 120 mm Hg. Gas B exerts
50 mm Hg. What pressure is exerted by gas C?
Omitted question:I think you mean Gas A and D each exert 120 mm Hg, if Gas D has a different value , just lug it into he equation as shown below and solve.
Answer:Gas C= 670mmHg
Explanation:
According to Dalton law of partial pressure
The total pressure of a mixture of gases is the sum of the pressures of each gas and can be illustrated as
Pressure total=P1+P2+… +Pn.
Total Pressure = Gas A + Gas B + Gas C + Gas D + Gas...
Now we have
Total Pressure = 120 mm Hg + 50mm Hg + Gas C + 120 mm Hg
960mmHg = 120 mm Hg + 50mm Hg + Gas C + 120 mm Hg
960mmHg =290mmHg +Gas C
Gas C =960mmHg -290mmHg
Gas C= 670mmHg
2.00g of Copper wire was added to 50.0 mL of a 0.050M solution of Silver Nitrate. The reaction
produced solid silver and aqueous copper II Nitrate. The silver precipitate was collected and
dried. It was determined that the mass of the silver precipitate was 0.24 g. Use this information
to determine the theoretical yield, limiting reactant, and percent yield.
Answer:
See explanation
Explanation:
Now, the equation of the reaction is;
Cu(s) + 2AgNO3(aq) --------> Cu(NO3)3 (aq) + 2Ag(s)
Number of moles of silver precipitate = 0.24/108 g/mol= 0.0022 moles
Number of moles of AgNO3 = 50/1000 * 0.050 = 0.0025 Moles
If 2 moles of AgNO3 yields 2 moles of Ag
Then 0.0025 moles of AgNO3 yields 0.0025 * 2/2 = 0.0025 moles of Ag
Number of moles of Cu = 2.00g/63.5 g/mol = 0.03 moles
If 1 mole of Cu yields 2 moles of Ag
0.03 moles of Cu yields 0.03 moles * 2/1 = 0.06 moles of Ag
Hence AgNO3 is the limiting reactant
Theoretical yield of Ag = 0.0025 moles of Ag * 108 = 0.27 g
Actual yield of Ag = 0.24 g
Percent yield = actual yield/theoretical yield * 100
Percent yield = 0.24/0.27 * 100
Percent yield = 88.8%
The temperature of a sample of gas in a steel tank at 60.0 kPa is increased from -105.0°C to 26.0
*C. What is the final pressure inside the tank?*
(
Answer:
106.785 kPa, I believe this is correct!
Explanation:
1, 2, or 3...help please
Answer:
molecular so number 3. ...
4) How many liters are needed for a 5.1 Molar solution containing 2.3 moles of NaCl?
moles =
Molarity =
Liters =
The measured pOH of a solution is 5.5. What is the hydrogen ion, [H+ ],
concentration?
First, calculate pH using the pOH:
14 - pOH = pH --> pH = 14 - 5.5 = 9.5
[H+] = 10^-pH = 10^-9.5 = 3.2 x 10^-10 M ≈ 3 x 10^-10 M (The answer should technically only be one sig fig, since the pOH is given to only one decimal place).
give an example of how an organism can use surface tension?
Answer:Insects, such as water striders, and spiders, such as fisher spiders, can glide or scamper across the surface of water. These critters are small enough that their weight can be supported almost entirely by surface tension, the relatively weak forces that hold water molecules together.
Explanation:
Answer:
Examples of surface tension Water striders are able to walk on top of water due to a combination of several factors. Water striders use the high surface tension of water and long, hydrophobic legs to help them stay above water. Water striders use this surface tension to their advantage through their highly adapted legs and distributed weight.
Explanation:
pls mark brainliest
when Henry mosléy came up with he's own atomic number?
I WILL MARK AS BR*NLIST IF YOU CORRECT ANSWER
Answer:
1911 is when he made it
Explanation:
Moseley's law provided a reasonably complete experimental set of data that supported the (new from 1911) conception by Ernest Rutherford and Antonius van den Broek of the atom, with a positively charged nucleus surrounded by negatively charged electrons in which the atomic number is understood to be the exact physical number of positive charges (later discovered and called protons) in the central atomic nuclei of the elements.
What are the products we get out of this
reaction? (check picture)
Explanation:
two compounds because element is the very smallest part of any mixture
Which of the following elements would have the greatest attraction for
electrons? *
Rb
sr
Cs
Ba
Answer:
Sr
Explanation:
because it's electronegativity is the highest.
A star's mass determines the A.length of its lifecycle b.location of the star c.galaxy it belongs to. D.shape of the star
Answer:
A.length of its lifecycle
Explanation:
A star will go through evolutionary stages depending on their initial mass. These stages are determined by the internal structure of the star and how it produces energy. Therefore, scientists may use the HR diagram to determine the length of the stars lifecycle depending upon its initial mass.
Ahhhh someone help me with this
Answer:
3.6g
Explanation:
2 moles of water gives 1 mole of oxygen
2(h2o)=1(o2)
2(molar mass of h2o)=1(molar mass of oxygen molecule)
2(18)=1(16×2)
36=32
3.6=x
cross multiply
3.6×32=36× x
115.2=36x
x=115.2÷36
x=3.6g
Which of the below will effect colligative properties the most?
Be3N2
OK₂S
CO
Mgs
Answer:
CO
Explanation:
How many spirals does a DNA molecule have?
Answer:
two
Explanation:
2
Answer:
two
Explanation:
nucleic acids are made up of chains of many repeating units called nucleotides. the dna molecule consists of two such chains that spiral around an imaginary axis to form a double helix (spiral.)
hope this helps :)
have a nice day !!
What is the scientific method? *
a. A series of steps used by scientists to investigate an hypothesis
b. A series of steps used to determine which chemicals are good for use
c. A series of steps used to tell how life began on earth
d. A series of steps used to by scientists to find about technology
How many atoms of hydrogen are in the compound 6(NH4)2CO3?
a tiny particle in the nucleus of an atom that is about the same size as a proton is a(n)
A. electron
B. neutron
C. solid
D. element
Answer:
b. neutron.
Explanation:
I hope this helps.
Answer:
B. Neutron
Explanation:
Neutrons are about the same size as protons. In addition, nuclei are made up of neutrons and protons. Electrons are located in the electron cloud, which is outside of the nucleus. Solids are hard matter, and an element is a substance that cannot be broken down any further.
Hope this helps!
Balance the following equation
C₂H₆O + O₂ → CO₂ + H₂O
Answer:
C2H6O + 3O2 - > 2CO2 + 3H20
How do living things (such as animals) affect the phosphorus cycle?
Explanation:
Phosphorus moves in a circle through rocks, water, soil and sediments and organisms. Over time, rain and weathering cause rocks to release phosphate ions and other minerals.When you straighten your leg, the muscles on top of your leg muscles on the bottom of your leg. Your answer
Answer:
your quad is the top part and your hamstring is the bottom part
Explanation:
fun fact the hamstring is one of the strongest muscles in the body
help please see attached file
Answer:
balanced equation of glucose
6CO2 + 6H2O----------C6H12O6 + 6O2
in the presence of sun light.
3.) 2.46 grams of Cu(NO3)2 would contain how many formula units?
Answer:
7.90×10²¹ formula units
Explanation:
From the question given above, the following data were obtained:
Mass of Cu(NO₃)₂ = 2.46 g
Formula units of Cu(NO₃)₂ =?
From Avogadro's hypothesis,
1 mole of Cu(NO₃)₂ = 6.02×10²³ formula units
Next, we shall determine the mass of 1 mole of Cu(NO₃)₂. This can be obtained as follow:
1 mole of Cu(NO₃)₂ = 63.5 + 2[14 + (3×16)]
= 63.5 + 2[14 + 48]
= 63.5 + 2[62]
= 63.5 + 124
= 187.5 g
Thus,
187.5 g of Cu(NO₃)₂ = 6.02×10²³ formula units
Finally, we shall determine the formula units contained in 2.46 g of Cu(NO₃)₂. This can be obtained as follow:
187.5 g of Cu(NO₃)₂ = 6.02×10²³ formula units.
Therefore,
2.46 g of Cu(NO₃)₂ =
(2.46 × 6.02×10²³)/187.5
= 7.90×10²¹ formula units
Thus, 2.46 g of Cu(NO₃)₂ contains 7.90×10²¹ formula units
The urinary bladder is a muscular organ of the excretory system that collects urine excreted by the kidney. How does the nervous system help the urinary system in excretion?
Explanation:
it helps in when the kidney has used the needful nutrients been taken then the unwanted waste product it sends it to the nervous system then the nervous system passes the waste product to the bladder in form of urine
What does the reaction rate say about a reaction?
O It tells what activation energy the reaction has.
O It tells if a catalyst was used in the reaction.
It tells how quickly products will be made.
It tells what the concentration of reactants is.
Previous
Answer:
It tells how quickly products will be made.
Explanation:
ap3
x
The reaction rate provides information about how quickly products will be made in a chemical reaction.
The reaction rate is a measure of how fast a chemical reaction proceeds over time. It provides information about the speed at which reactants are consumed and products are formed during a reaction. The reaction rate is typically expressed as the change in concentration of a reactant or product per unit of time.
The reaction rate is influenced by various factors such as the nature of the reactants, concentration of reactants, temperature, surface area, and the presence of catalysts. By measuring the reaction rate, scientists can gain insights into the kinetics of a reaction and understand the factors that affect its speed.
The reaction rate is particularly important because it allows us to predict and control the rate at which products are formed. It is useful in various applications, including industrial processes, pharmaceutical development, and environmental studies. By manipulating the reaction conditions, such as adjusting the concentration of reactants or introducing a catalyst, we can alter the reaction rate to achieve desired outcomes.
In summary, the reaction rate provides valuable information about the speed at which products are formed in a chemical reaction, allowing us to understand and control the kinetics of the process.
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The reaction is carried out at a high temperature to provide the reactant with activation energy.what is activation energy?
Answer:
Activation energy, in chemistry, the minimum amount of energy that is required to activate atoms or molecules to a condition in which they can undergo a chemical transformation or physical transport.
When calcium chloride is added to a sample of water, the boiling point will _________. A. increase B. decrease C. not change D. first decrease, then increase
Answer:
C
Explanation:
If you add salt to water, its boiling point increases.
When calcium chloride is added to a sample of water, the boiling point will increase. Option A is correct.
What is boiling point?The boiling point of the liquid is the temperature at which the vapor pressure of a given liquid equals the external pressure or atmospheric pressure surrounding the given liquid.
The calcium chloride is added to a sample of water it releases the some amount heat and become exothermic and the boiling point will increase due to the reaction of water and calcium chloride.
Therefore, when calcium chloride is added to a sample of water, the boiling point will increase. Option A is correct.
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The image shows the mouth of a Tasmanian devil. The Tasmanian devil has four distinctive long teeth near the front of its mouth. Based on their shape, what are these teeth mostly like used for?
A.
holding and tearing meat
B.
crunching and crushing bone
C.
grinding up plant material
D.
rooting in soil for worms
Answer:
same as the answer of her
Explanation:
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What happens during high tide?
a.The tidal range is at its minimum in a location.
b.The tidal range is at its maximum in a location.
c.The water level in the ocean rises to above average water level.
D.The water level in the ocean drops to below average water level.
Answer: c
Explanation:
According to periodic trends, at which position on the periodic table would
an element most likely have an electronegativity HIGHER than that of calcium?
Select ALL correct answers.
Answer:
Just to the right of calcium
Explanation:
Electronegativity increases as we go from left to right the periodic table