Answer: B. To determine which of the two pills is a better choice for treating a disease
Explanation: A placebo will have no effect thus comparing it with a drug would be obsolete.
Answer:
So that all patients will believe there disease is being treated
Explanation:
APEC!
What happens inside a can of spoiled food as gas is produced?
A. The pressure decreases.
B. The temperature increases.
C. The volume decreases.
D. The pressure increases.
Answer:D the pressure increases
Explanation:
Answer: D
Explanation:
the pressure increases
A buffer solution contains 0.345 M acetic acid and 0.377 M sodium acetate . If 0.0613 moles of potassium hydroxide are added to 250 mL of this buffer, what is the pH of the resulting solution ? (Assume that the volume does not change upon adding potassium hydroxide. )
Answer:
pH = 5.54
Explanation:
The pH of a buffer solution is given by the Henderson-Hasselbach (H-H) equation:
pH = pKa + log[tex]\frac{[CH_3COO^-]}{[CH_3COOH]}[/tex]For acetic acid, pKa = 4.75.
We calculate the original number of moles for acetic acid and acetate, using the given concentrations and volume:
CH₃COO⁻ ⇒ 0.377 M * 0.250 L = 0.0942 mol CH₃COO⁻ CH₃COOH ⇒ 0.345 M * 0.250 L = 0.0862 mol CH₃COOHThe number of CH₃COO⁻ moles will increase with the added moles of KOH while the number of CH₃COOH moles will decrease by the same amount.
Now we use the H-H equation to calculate the new pH, by using the new concentrations:
pH = 4.75 + log[tex]\frac{(0.0942+0.0613)mol/0.250L}{(0.0862-0.0613)mol/0.250L}[/tex] = 5.54How do I balance coefficient equations
Answer:
In order to balance the chemical equation, you need to make sure the number of atoms of each element on the reactant side is equal to the number of atoms of each element on the product side. In order make both sides equal, you will need to multiply the number of atoms in each element until both sides are equal.
Answer: When you balance a chemical equation, you change coefficients. You never change subscripts. A coefficient is a whole number multiplier. To balance a chemical equation, you add these whole number multipliers (coefficients) to make sure that there are the same number of atoms on each side of the arrow.
Explanation:
how many mols of Ti is 3.15 * 10^23 atoms of Titanium
Answer: There are 0.523 moles of Titanium in [tex]3.15\times 10^{23}[/tex] atoms of Titanium
Explanation:
According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given atoms}}{\text {avogadro's number}}[/tex]
[tex]\text{Number of moles of Titanium}=\frac{3.15\times 10^{23}}{6.023\times 10^{23}}=0.523moles[/tex]
PLEASE HELP What's the mass in grams of 0.442 moles of calcium bromide, CaBr2? The atomic
weight of Ca is 40.1 and the atomic weight of Br is 79.9.
A) 452.3 g
B) 53.04 g
C) 44.2 g
D) 88.4 g
Answer: Thus there are 88.4 g of calcium bromide.
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to the molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
Molar mass of = 40.1 (1)+ 2(79.9) = 199.9
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]
[tex]0.442=\frac{x}{199.9}[/tex]
[tex]x=88.4g[/tex]
Thus there are 88.4 g of calcium bromide.
FOR BRAINLIST!!!
A Student 1
B Student 2
C Student 3
D Student 4
Answer:
Student 2
Explanation:
I am not 100% sure but I would say Student 2
:)
i agree with the other answer
how many atoms of N are in 5.6g of N?
Answer:
ᵐʸ friend ʰᵉʳᵉ ʲᵘˢᵗⁱⁿ ʰᵉˢ already taken ᵃⁿᵈ hes ᶜʳᵃᶜᵏᵉᵈ ᵃᵗ ᶠᵒʳᵗⁿⁱᵗᵉ my guy Uhhh
Explanation:
On a scale of 1️⃣ to , you’re a 9️⃣. I’m the 1️⃣ you need.
Your friend John is having trouble with his compost bin. The material in his compost pile doesn't seem to be decomposing
well. You take a sample of the pole and check for the presence of microorganisms under the microscope You see that there
are indeed microorganisms, however, they don't appear to be growing very fast John says that he regularly mixes his
compost pile to expose it to oxygen What is the most likely explanation for this problem?
The temperature may not be high enough to encourage microorganism growth
Inorganic materials may have been included in the compost pile
The temperature may be too high for microorganisms to tolerate
Inappropriate food waste may have been included in the compost pile
i) __________are rigid due to strong (ii)___________ of attraction between the particles
Answer:
Liquid Solids are rigid due to strong glass of attraction between the particles.
Explanation:
Why is boiling water a physical change
Answer:
it is cleaning the water and heating it
Answer:
When boiling the water, the water will begin to evaporate and thats the physical change.
Fish, amphibians, reptiles, birds, and mammals have similar embryos. They all start with gill slits. Fish and some amphibians grow to have gills. Some amphibians, reptiles, birds, and mammals develop lungs to breathe air
They all start with tails. Fish, some amphibians, reptiles, and birds grow tails. Humans do not keep their tails.
Fish and reptiles develop scales. Amphibians, birds, and humans have skin. Birds have feathers, and humans have hair. With which animal do humans exhibit the most linear relationship?
birds
amphibians
reptiles
fish
Answer:
Birds
Explanation: They are both mammals
Answer:
birds
Explanation:
before phase change: molecules move around each other 15. The medicine in the diagram above has molecules that are moving around each other. The doctor needs to slow down the molecules enough to cause a phase change. How will she do this, and how will this affect the medicine? I She transfers energy ... a into the medicine until it is a liquid. b) into the medicine until it is a gas. C out of the medicine until it is a solid. d out of the medicine until it is a liquid. LE 1 21 Illuminate Education, Inc.
Answer:
She transfers energy out of the medicine until it is solid. So the answer would be C.
Explanation:
According to the forces of attraction , molecules can be slowed down by moving out of the medicine until it is a solid , it will decrease the rate of absorption of medicine.
What are forces of attraction?Forces of attraction is a force by which atoms in a molecule combine. it is basically an attractive force in nature. It can act between an ion and an atom as well.It varies for different states of matter that is solids, liquids and gases.
The forces of attraction are maximum in solids as the molecules present in solid are tightly held while it is minimum in gases as the molecules are far apart . The forces of attraction in liquids is intermediate of solids and gases.
The physical properties such as melting point, boiling point, density are all dependent on forces of attraction which exists in the substances.
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what is fermentation
Fermentation is a metabolic method that creates chemical changes in natural substrates through the action of enzymes.
Explanation: hope this helps :)
Question 21 of 25
Which of the following best describes an Arrhenius acid-base reaction?
O A. Acid + base = H+ + OH-
B. Acid + base = salt + water
C. Acid + base = conjugate base + conjugate acid
D. Acid + base =
H20
Answer:
B. Acid + base = salt + water
Explanation:
In accordance to the proposal of a scientist called Svante Arrhenius, an acid is a substance that increases the H+ concentration of a solution by dissociating into it while the base increases the OH- concentration of a solution by dissociating into it. Furthermore, Arrhenius stated that this two ions combine in an aqueous solution to give water.
Hence, Arrhenius acid-base reaction is the combination of an acid and base to produce salt and water as products. That is; Acid + base = salt + water.
what is full from of DTP
Answer:
Hellloooo
ur answer is
Desktop Publishing.
Explanation:
thanks hope it helps
what is the reaction type for Zn(C2H3O2)2 + Na3(PO4)?
Answer: This is a precipitation reaction: Zn 3(PO 4) 2 is the formed precipitate.
Explanation:
Go this Answer form, (chemequations.com)
Im Glad I helped! =)
What is the correct IUPAC name for Al(IO₃)₃?
Answer:
Aluminum Iodate
The IUPAC name of Al(IO3)3 is diiodyloxyalumanyl iodate.
What is IUPAC name ?The systematic method of nomenclature of the organic or inorganic compound on the basis of International Union of Pure and Applied Chemistry.
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Which describes the polarity in a water molecule?
A. partial negative charge on the oxygen atom because its electrons are pulled toward the hydrogen atoms
B. partial negative charge on the oxygen atom because it pulls electrons from the hydrogen atoms
C. partial positive charge on the oxygen atom because it pulls electrons from the hydrogen atoms
D. partial positive charge on the oxygen atom because its electrons are pulled toward the hydrogen atoms
The answer is B
Answer:
B. partial negative charge on the oxygen atom because it pulls electrons from the hydrogen atoms
Explanation:
Oxygen has a charge of 6 so they need to pull 2 electrons from hydrogen, which creates a partial negative charge.
A cylinder, with a piston pressing down with a constant pressure, is filled with 1.90 moles of a gas (n1),
and its volume is 40.0 L (V1). If 0.400 mole of gas leak out, and the pressure and temperature remain the
same, what is the final volume of the gas inside the cylinder?
Answer:
31.58 L
Explanation:
From the question given above, the following data were obtained:
Initial mole (n₁) of gas = 1.90 moles
Initial volume (V₁) = 40 L
Final mole (n₂) = 1.90 – 0.40 = 1.5 moles
Final volume (V₂) =.?
The final volume of the gas can be obtained as follow;
V₁ / n₁ = V₂ / n₂
40 / 1.9 = V₂ / 1.5
Cross multiply
1.9 × V₂ = 40 × 1.5
1.9 × V₂ = 60
Divide both side by 1.9
V₂ = 60 / 1.9
V₂ = 31.58 L
Thus, the final volume of the gas is 31.58 L
Determine the number of grams of carbon-14 remaining in this sample at 17,100 years.
Answer: I need help
Explanation:
how many grams of carbon tetrachloride can be produced from reacting 709.0 grams of chlorine (CI2) with excess methane?
C2H6 + Cl* => C2H5* + HCl
Answer:
C2H6 + Cl → C2H5 + HCl
equation is balanced
3.2
Differentiate between a Merger and Alliance
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EXPLANATION:
Alliance is an approach in which two or more companies agree to pool their resources together to form a combined force in the marketplace. Unlike a merger, an alliance does not involve the emergence of a new combined entity. ... The joint venture is a very popular form of an alliance.
Answer:
Alliance is an approach in which two or more companies agree to pool their resources together to form a combined force in the marketplace. Unlike a merger, an alliance does not involve the emergence of a new combined entity. ... The joint venture is a very popular form of an alliance.
Select the structure that corresponds
to the name:
3,5,6-trichloro-2-heptanol
Answer:C both
Explanation:
The Structure that correspondsto the name: 3,5,6-trichloro-2-heptanol is C both.
How nomenclature is done in organic compound ? First name the principal carbon chain and also check type of bonds single or double present on the carbon chain. Name the functional group according to Seniority table. Name the substituent alphabetically. Both are isomers∵ all are substituent and OH alcohol is added on the principal carbon chain both names are suggested.
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Some students decide to plant their own garden. They want to eat a more plant-based diet For meat, they will buy locally from a butcher. Any remaining scraps will be composted and used as fertilizer for their garden Which part of this plan represents recycling to reduce their waste?
composting scraps
planting a garden
eating a plant-based diet
buying locally
Answer:
composting scraps
recycling is the action or process of converting waste into reusable material.
An aluminum pan and a copper pan have the same mass and are heated to the same temperature. Which will feel hotter?
Answer:
The copper pan!
Explanation:
Copper conducts heat well because its atoms contain only one free valence electrons in the outer shell. Elements with a low number of valence electrons transfer heat the best, and copper has only one. Valence electrons move about freely.
Good luck on your assignment!
What is the double bond?
Answer:
a chemical bond in which two pairs of electrons are shared between two atoms.
More than half of the elements are in which state of matter at room temperature?
What happens to the atomic mass when the atomic numbers increase?
Which elements does not belong to a main group of elements?
Please help I really need help!!
Answer:gas
Explanation:
How is sedimentary rocks formed?
Answer:
Sedimentary rocks are formed when sediment is deposited out of air, ice, wind, gravity, or water flows carrying the particles in suspension
Explanation:
What happens after coral is bleached?
It dies immediately
It produces peroxides
It is susceptible to starvation
It releases algae into the ocean
Explanation:
The Answer Is
That The Coral Releases Its Colours And Becomes Pale White