Answer:
study a larger sample size than before.
Explanation:
Science is evolving day by day and every new experiment is contradict the old experiment, giving new theories.
The advancement in the technology modifying the new experimental methods and it can change a theory if study a larger sample size than before. It is so because new experiment verify and validates larger sample size and evidences can contradict the old theory. Large sample size means more experiments and more validations.
Hence, the correct answer is "study a larger sample size than before."
Answer: is the D
Explanation:
Can someone help me on this please
Answer:
the answer for 5 is liquid
What is one role of the American Heart Association?
Answer:approving new heart medications for public use
Explanation:
The following chemical reaction takes place in aqueous solution:
ZnBr2(aq)+2 NaOH(aq) --Zn(OH),(s)+2 NaBr(aq)
Write the net ionic equation for this reaction.
Answer:
[tex]{\rm Zn^{2+}}\, (aq) + {\rm 2\; OH^{-}}\, (aq) \to {\rm Zn(OH)_2}\, (s)[/tex].
Explanation:
Ionic Equation for this reactionRewrite only the species that exist as ions. Those species typically include:
soluble salts,strong acids, and soluble bases.In this reaction, both [tex]{\rm ZnBr_2}\, (aq)[/tex] and [tex]{\rm NaBr}\, (aq)[/tex] are salts. The state symbol "[tex](aq)[/tex]" suggests that both of these salts are soluble. Hence, both of these salts exist as ions and should be rewritten:
Each [tex]{\rm ZnBr_2}\, (aq)[/tex] formula unit would exist as one [tex]{\rm {Zn}^{2+}}\, (aq)[/tex] and [tex]2\; {\rm Br^{-}}\, (aq)[/tex]. Notice how there are twice as many [tex]{\rm Br^{-}}[/tex] ions as [tex]{\rm {Zn}^{2+}}[/tex] ions.Each [tex]{\rm NaBr}\, (aq)[/tex] formula unit would exist as one [tex]{\rm Na^{+}}\, (aq)[/tex] and one [tex]{\rm Br^{-}}\, (aq)[/tex].Similarly, the state symbol "[tex](aq)[/tex]" suggests that the base [tex]\rm NaOH[/tex] is also soluble:
Each [tex]{\rm NaOH}\, (aq)[/tex] formula unit would exist as one [tex]{\rm Na^{+}}\, (aq)[/tex] and one [tex]{\rm OH^{-}}\, (aq)[/tex].On the other hand, the state symbol "[tex](s)[/tex]" suggests that the base [tex]{\rm Zn(OH)_2}\, (s)[/tex] is a precipitate and is not soluble. Rather, the bonds within [tex]{\rm Zn(OH)_2}[/tex] stay mostly intact, and this species would not exist as ions. Hence, do not rewrite [tex]{\rm Zn(OH)_2}\, (s)\![/tex] when deriving the ionic equation for this reaction.
Hence, the ionic equation for this reaction would be:
[tex]\begin{aligned}&\underbrace{{\rm Zn^{2+}}\, (aq) + 2\, {\rm Br^{-}}\, (aq)}_{\text{from ${\rm ZnBr_2}\, (aq)$}} + \underbrace{2\, {\rm Na^{+}}\, (aq) + 2\, {\rm OH^{-}}\, (aq)}_{\text{from $2\, {\rm NaOH}\, (aq)$}} \\ & \to \underbrace{{\rm Zn(OH)_2}\, (s)}_{\text{precipitate}} + \underbrace{2\, {\rm Na^{+}}\, (aq) + 2\, {\rm Br^{-}}\, (aq)}_{\text{from $2\, {\rm NaBr}\, (aq)$}}\end{aligned}[/tex].
Net Ionic Equation for this reactionEliminate species that are present on both sides of the ionic equation to obtain the net ionic equation. A species should be eliminated if only if an equal number of this species are found on both sides of the ionic equation. Otherwise, subtract from the side with a larger number of that species.
For this reaction, the net ionic equation would be:
[tex]{\rm Zn^{2+}}\, (aq) + {\rm 2\; OH^{-}}\, (aq) \to {\rm Zn(OH)_2}\, (s)[/tex].
Complete the following sentence: In a reaction containing two reactants, if one of the reactants is in excess, the other reactant is known as the ______ reactant.
Answer:
excess reactant
Explanation:
The excess reactant is the reactant in a chemical reaction with a greater amount than necessary to react completely with the limiting reactant. It is the reactant(s) that remain after a chemical reaction has reached equilibrium.
In a reaction containing two reactants, if one of the reactants is in excess, the other reactant is known as the limiting reactant which decides the yield of the reaction.
What is limiting reactant ?In a reaction, all the reactants have to be in correct stoichiometry to complete the reaction. To achieve the mole ratio of the reactants is very much important for the completion of a reaction.
If a reactant is insufficient in amount, then the reaction will stop as soon as this reactant is consumed. Hence, this reactant determine the yield of the product. This reactant which is not in correct stoichiometry for the complete reaction is called the limiting reactant.
The reactant which is excess in quantity thus does not have a role in the yield of the reaction is called the excess reactant. Whatever, the concentration of this reactant in extra, the reaction does not proceed after the consumption of limiting reactant.
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When a fluorine atom becomes an ion, it will
A) gain an electron and increase in size
B) lose an electron and increase in size
C) gain an electron and decrease in size
D) lose an electron and decrease in size
Answer:
A) gain an electron and increase in size
Explanation:
Fluorine is a Group 17 element, making it a halogen. This means that it has 7 valence electrons in its outer shell. It only needs one more electron to fill its outer shell and gain stability. When fluorine becomes an ion, it gains an electron and becomes F⁻. Adding electrons creates a larger ion because the electrons occupy a larger volume due to mutual repulsions pushing them apart.
Hope that helps.
When a fluorine atom becomes an anion, it will gain an electron and increase in size. Therefore, option (A) is correct.
What is an ion?An ion is a chemical specie that holds a positive or negative charge. The term ‘ion’ refers to atoms or molecules with non-zero net charges associated with them. Therefore, all ions have either a greater number of electrons than protons in their atomic structures or a greater number of protons than electrons.
If the number of protons is greater than electrons are termed to hold a net positive charge and are commonly referred to as cations. The ions that contain a greater number of electrons than protons hold a net negative charge and are known as anions.
The electronic configuration of the fluorine is 1s²2s²2p⁵. As the fluorine atom accepts one electron in its valence shell it becomes anion F⁻. The number of protons is less than electrons therefore effective nuclear charge decreases and the size of the ion increases.
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A regular jet flying at 530 mi/ hr travels from New York to London in 7 hrs. What is the distance between the two cities?
Answer:
3710 miles
Explanation:
I cant describe
balance the equation
____ NH4OH + ____ H3PO4 ____ (NH4)3PO4 + ____ H2O
Answer:
3NH4OH + H3PO4 -----> (NH4)3PO4 + 3H2O
Explanation:
L.H.S
3NH4OH + H3PO4
N = 3H = 18O = 7P = 1R.H.S
(NH4)3PO4 + 3H2O
N = 3H = 18O = 7P = 19. t An element that has only 5 electrons in the 4p orbital is located in which group? A. O Group 1 B. Group 17 C. O Group 2 D. Group 8
Answer:
B. Group 17
Explanation:
The element is Bromine. Its electron configuration is:
1s2 2s2p6 3s2p6d10 4s2p5
You can see that its last orbital is 4p^5 for 5 electrons in the 4p orbital.
For species that reproduce asexually, all their offspring are
A. genetically identical
B. genetically different
C. almost identical
D. slightly different
Answer:
A. genetically identical
Explanation:
Asexual reproduction produces offspring that are genetically identical to the parent because the offspring are all clones of the original parent. A single individual can produce offspring asexually and large numbers of offspring can be produced quickly
All the offspring that are produced in the process are genetically identical.
When we talk about this mode of reproduction, we talk about a mode of reproduction in which an organism reproduces without the fusion of gametes. This occurs essentially by cell division.
When this occur, there is no crossing of genetic material as such, all the offspring that are produced in the process are genetically identical.
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You need to make an aqueous solution of 0.197 M barium nitrate for an experiment in lab, using a 500 mL volumetric flask. How many grams of solid barium nitrate should you add?
Answer:
Mass of barium nitrate needed = 25.74 g
Explanation:
Given data:
Molarity of solution = 0.197 M
Volume of solution = 500 mL (500 mL× 1 L /1000 mL = 0.5 L)
Mass of barium nitrate needed = ?
Solution:
Molarity = number of moles of solute / volume in L
0.197 M = number of moles of solute / 0.5 L
Number of moles of solute = 0.197 mol/L ×0.5 L
Number of moles of solute = 0.0985 mol
Mass of barium nitrate:
Mass = number of moles × molar mass
Mass = 0.0985 mol × 261.32 g/mol
Mass = 25.74 g
Can someone help with these
How many molecules of water of water are in a 821.3 g sample
Answer: 2.744 x 1025 molecules
Which three elements are combined in cslcium nitrate?
Answer: calcium, nitrogen and oxygen
Explanation:
What are the three main parts of an atom and what are their charges?
Where are the electrons found in an atom?
Answer:
Three main parts are Protons (pos charge) Neutrons (no charge) Electrons (negative charge) and the electron is found on the outside of the nucleus
Explanation:
need a quick answer please
Answer:
I think it B
Explanation:
help PLZ will give brainliest
Answer:
6.Crust
7. outer core
8.mantle
What is one bad thing that can happen when humans build more and more streets and buildings?
Answer:
there will be less and less space
Explanation:
after a certain pesticide compound is applied to crops its decomposition is a first order reaction with a half life of 56 days. what is the rate constan for the decomposition reacion
Answer:
Rate constant = 0.01238 days⁻¹
Explanation:
The first order reaction has as general equation:
Ln[A] = -kt + Ln[A]₀
Where [A] is concentration of the reactant after time t,
k is rate constant
And [A]₀ the initial concentration of the reactant
The half-life is the time required to reach the half of the initial concentration. If [A]₀ = 1; [A] = 1/2
Replacing:
Ln[1/2] = -kt + Ln[1]
-0.693 = -k*56days
0.01238days⁻¹ = k
Rate constant = 0.01238 days⁻¹
Calculate the percent composition of Fe in Fe(OH)3
Answer:
52.257%
Explanation:
"Potassium sulfide is reacted with nitric acid."
Identify the type of the reaction.
Explanation:
K2S + 4HNO3 → 2KNO3 + 2NO2 + S + 2H2O. Potassium sulfide react with nitric acid to produce potassium nitrate, nitrogen dioxide, sulfur and water. Nitric acid - concentrated
PLEASE MARK AS BRAINLIEST
The reaction of Potassium sulfide with nitric acid is a double displacement reaction.
What is displacement reaction?A displacement reaction can be defined as one wherein a set of atoms is displaced by another atom in a molecule. For example, when the iron metal is added to a solution of copper sulfate, it displaces the copper metal.
[tex]A + BC \longrightarrow AC + B[/tex]
A single displacement reaction can be described as a kind of oxidation-reduction reaction when an element moves out of a compound, one element is replaced by the other in a compound.
Double displacement reactions occur mostly in aqueous solutions wherein the ions precipitate and the exchange of ions takes place. The double displacement reaction can be represented as:
[tex]AB+CD\longrightarrow AC+ BD[/tex]
The reaction between the potassium sulfide and nitric acid gives hydrogen sulfide and potassium nitrate.
[tex]K_2S (aq) + 2HNO_3 (aq) \longrightarrow H_2S(g) + 2KNO_3(aq)[/tex]
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3 In the section describing protozoa, the author states: "Protozoa are germs that live in almost all soil, including the hot desert sand. They live in all water too. The reader can infer that protozoa can be found where? A only in oceans and on beaches B never in bodies all water and most soil mostly in warm climates
Answer:
I believe the answer is A.
Explanation:
This section states that protozoa live in all bodies of water therefore B can not be an answer because it says protozoa dose not live in any body of water.
I hope this answers your question.
Why does Sodium bond with Chlorine???
Answer:
Explanation:
Sodium has 1 electron in its outermost shell, and chlorine has 7 electrons. ... If sodium can transfer it's "spare" electron to chlorine (as shown above), both atoms will satisfy their full outer shell requirements, and an ionic bond will be formed. They combine as atoms, and separate as ions. When sodium and chlorine atoms come together to form sodium chloride (NaCl), they transfer an electron. ... Because the sodium ion has a positive charge, and the chlorine ion has a negative charge, they are attracted to each other, and form an ionic bond.
When a sodium atom transfers an electron to a chlorine atom, forming a sodium cation (Na+) and a chloride anion (Cl-), both ions have complete valence shells, and are energetically more stable. ... The reaction is extremely exothermic, producing a bright yellow light and a great deal of heat energy.
Compared to a potassium atom, a potassium ion has
Explanation:
has lost 1 electron. Therefore, a potassium ion has a smaller radius since it has less electrons.
Please help with this
what is the mass of 1.75 moles of HF?
Answer:
Mass = 35.02 g
Explanation:
Given data:
Number of moles = 1.75 mol
Mass of HF = ?
Solution:
Formula:
Mass = number of moles × molar mass
Molar mass of HF = 20.01 g/mol
by putting values,
Mass = 1.75 mol × 20.01 g/mol
Mass = 35.02 g
Mapping the ocean floor did not provide any new evidence for the theory of continental drift.
True
False
What kind of reaction is symbolized by AB + C → CB + A?
A. Single replacement
a
B. Double replacement
C. Decomposition
D. Synthesis
SUBMIT
Since a single replacement reaction involves the change of an atom by another, the reaction is a single replacement reaction.
What is a reaction?The term chemical reaction is another word for chemical change. It involves an interaction between two or more chemical species leading to the formation of a new chemical species.
The reaction AB + C → CB + A is a single replacement reaction because The A in the reactant side is replaced by C while it becomes displaced.
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Answer:
single displacement
Explanation:
trust
All of the devices below either use or produce electrical energy. Which one converts mechanical energy to electrical energy?
E.Battery
F.Electrical drill
G.Wind turbine
H.Electric guitar
Answer:
G wind turbine
Explanation:
they get mechanical energy fron the wind the turns into electrical energy
Answer:
G is correct
Explanation:
just saying
HELP LIKE HELP HURRY I HAVE 2 hours. To finish
Answer: hello, the answer would be rotates, revolves
hope this helps :)
Explanation:
Cellular respiration takes place in the______.
Answer:
In the Mitochondrion
Explanation: