Answer:
sorry but i dont know it but you can ask me other things
Which of the following best explains why the
Gastropod is not a good example of an index
fossil?
Answer:
Since the gastropod is not unique, it cannot be an index fossil. An index fossil must be found over a wide area of the Earth. Since the gastropod is widely spread, it cannot be an index fossil.
Explanation:
Which of the following best describes an Arrhenius acid-base reaction?
Answer:
A. Acid + base = salt + water
Explanation:
correct for a pex
The correct option is (a) Acid + base = salt + water .
Sweden's Svante Arrhenius proposed the concept of acids and bases in 1884 based on the theory of ionization. According to Arrhenius, acids are hydrogen-containing compounds that release H + ions or protons when dissociated in water, and bases are hydroxide compounds that release OH-ions when dissociated in water. Acid + base = salt + water Neutralisation is a reaction between an acid and an alkali that forms a salt and water. Salts are odourless and have a salty taste, and many are soluble in water. Common examples include sodium chloride, potassium iodide, calcium carbonate and copper sulfate. The pH scale is used to measure acidity and alkalinity.Learn more about Neutralisation here https://brainly.com/question/23008798
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is soil a pure or impure substance?
Please help!!! I can’t figure it out!
Answer:
The third answer
Explanation:
How much energy would be required to heat 10.0 g of water at 0 degrees C to 100 degrees C,and change it into steam at 100 degrees C
Answer:
Q = 4180 J
Explanation:
Given data:
Mass of water = 10.0 g
Initial temperature = 0°C
Final temperature = 100°C
Heat required = ?
Solution:
Specific heat capacity of water is 4.18 j/g.°C.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 100°C - 0°C
ΔT = 100°C
Q = 10.0 g ×4.18 j/g.°C × 100°C
Q = 4180 J
Which best describes the current model of the atom?
O A a central nucleus containing protons with electrons orbiting in specific paths
O B. a solid sphere unique for everything that exists
O c a solid sphere with electrons and protons embedded
O D. a central nucleus containing protons and neutrons with electrons orbiting in levels of high probability
Explanation:
i think the answer might be D
Un móvil se mueve con movimiento acelerado. En los segundo 2 y 3 los espacios recorridos son 90 y 120 m, Calcula la velocidad inicial y su aceleración
Answer:
La velocidad inicial es 55 [tex]\frac{m}{s}[/tex]y su aceleración es -10 [tex]\frac{m}{s^{2} }[/tex]
Explanation:
Un movimiento es rectilíneo uniformemente variado, cuando la trayectoria del móvil es una línea recta y su velocidad varia la misma cantidad en cada unidad de tiempo . Dicho de otra manera, este movimiento se caracteriza por una trayectoria que es una línea recta y la velocidad cambia su módulo de manera uniforme: aumenta o disminuye en la misma cantidad por cada unidad de tiempo. Y la aceleración es constante y no nula (diferente de cero).
En este caso la posición del objeto esta dada por la expresión:
[tex]x=x0+v0*t+\frac{1}{2} *a*t^{2}[/tex]
donde x es la posición del cuerpo en un instante dado, x0 la posición en el instante inicial, v0 la velocidad inicial y a la aceleración.
En este caso, por un lado podes considerar:
x= 90 mx0= 0 mv0= ?t= 2a= ?Reemplazando obtenes:
[tex]90=v0*2+\frac{1}{2} *a*2^{2}[/tex]
[tex]90=v0*2+\frac{1}{2} *a*4[/tex]
[tex]90=v0*2+2*a[/tex]
Y por otro lado tenes:
x= 120 mx0= 0v0= ?t= 3a= ?Reemplazando obtenes:
[tex]120=v0*3+\frac{1}{2} *a*3^{2}[/tex]
[tex]120=v0*3+\frac{1}{2} *a*9[/tex]
[tex]120=v0*3+\frac{9}{2} *a[/tex]
Por lo que tenes el siguiente sistema de ecuaciones:
[tex]\left \{ {{2*v0+2*a=90} \atop {3*v0+\frac{9}{2} *a=120}} \right.[/tex]
Resolviendo por el método de sustitución, que consiste en aislar en una ecuación una de las dos incógnitas para sustituirla en la otra ecuación, obtenes:
Despejando v0 de la primera ecuación:
[tex]v0= \frac{90-2*a}{2}[/tex]
Reemplazando en la segunda ecuación:
[tex]120=\frac{90-2*a}{2} *3+\frac{9}{2} *a[/tex]
Resolviendo:
[tex]120=(90-2*a)*\frac{3}{2} +\frac{9}{2} *a[/tex]
[tex]120=135-3*a +\frac{9}{2} *a[/tex]
[tex]120-135=-3*a +\frac{9}{2} *a[/tex]
[tex]-15=\frac{3}{2} *a[/tex]
[tex]\frac{-15}{\frac{3}{2} } =a[/tex]
-10=a
Reemplazando el valor de a en la expresión despejada anteriormente obtenes:
[tex]v0= \frac{90-2*(-10)}{2}[/tex]
Resolviendo:
[tex]v0= \frac{90+20}{2}[/tex]
[tex]v0= \frac{110}{2}[/tex]
v0=55
La velocidad inicial es 55 [tex]\frac{m}{s}[/tex]y su aceleración es -10 [tex]\frac{m}{s^{2} }[/tex]
Describe the ammonium ion, NH4+, and the sulfate ion, SO42-. What compounds would these ions form with potassium and fluoride ions? Write the formula units for the resulting compounds.
Explanation:
Ammonium Fluoride and Potassium Sulphate
What does it mean when there is a physical change?
Question 1 options:
A new substance has been formed.
Matter has changed size, shape or form.
Matter has changed from one substance into another.
Matter has changed on the molecular level.
Answer:
The matter has changed size, shape, or form.
Explanation:
A new substance that is formed is creation.
if the matter changed from one substance to another this is called a chemical reaction.
Surely not. It won't change the molecular level.
Hope that helps.
CAN SOMEONE THATS GOOD AT CHEM PLEASE HELP ME?!?!
I’LL GIVE 50 POINTS!!!
AND A BRAINIEST!!!
PLEASE I HAVE OTHER HW TO DO:(
Answer:
Explanation:
1. q=mcat
q = (20)(4.184)( 30-20)
q = 836.8
Metal X displaces metal Y. Metal Z does not react with X or Y. What is the correct order of decreasing reactivity for metals X, Y, and Z?
Answer:
Metals on top of the activity series can displace metals at the bottom and they are highly reactive as compared to metals at the bottom of the series.
Hence, the order is X>W>Y>Z.
Please help any expert be sure your 100% correct please THANK YOU SO MUCH! ANY TEACHER PLEASE HELP!! THIS IS SCIENCE PLEASE EXPLAIN IT TO ME!!!
What causes high and low tides?
O A. Variations in salinity and temperature transmit waves across the
ocean.
B. As Earth rotates, the moon's gravity pulls on different parts of the
planet.
C. Ocean water is driven by differences in water density.
D. Underwater disturbances displace large amounts of water.
SUBMIT
Would it be possible for electrons in the 2p orbitals to be inside the 2s orbital?
(Please explain)
Answer:
Yes
Explanation:
You can have 2s and have part of the 2p of the row in the p section.
How can we predict melting points?
Explanation:
Many of the properties of organic molecules can be predicted based on the strength of their cohesive molecule-molecule interactions (i.e. how much the molecules want to stick together). The boiling point (BP) and melting point (MP) of an organic molecule is related to: 1) the molecular weight of the molecule and 2) the "stickiness" of individual molecules for their neighbors.
For example, molecules in a liquid are held together by attractive interactions between molecules. These interactions must be broken (by adding heat) in order to transition into the gas. The stronger the cohesive interactions, the more heat that is necessary for the liquid-to-gas phase transition. These same attractive molecule-molecule interactions have to be broken for a solid to liquid phase change.
Examples: (Rank the following molecules in terms of MP and BP.)
Introduction to intermolecular forces:
All of the attractive intermolecular forces are based on the electrostatic attraction of positive charges on one molecule with negative changes. The stronger the charges, the stronger the attraction between molecules.
How to:
In general, comparisons can only be made between molecules with similar formulas or molecular weights.* First, identify the functional groups in the molecules being compared. Each functional group can form different types of intermolecular interactions (see the chart above). Interactions higher up on the chart form stronger cohesive interactions and will have higher boiling points and melting points.
* Note that larger molecules usually have higher boiling points and melting points. This is not because of their higher molecular weights but because they usually have greater surface areas with which to form more intermolecular interactions. This is also why linear molecules tend to have higher MPs and BPs than branched (or more spherically shaped) molecules. Linear molecules will have more surface area than a more spherically shaped molecule.
All three molecules have approximately the same molecular formula and molecular weights. Only molecule A contains a strongly polarized or ionic functional group: an aldehyde. The C=O group in aldehydes generate a strong molecular dipole (partial + and - charges). Thus, it can form weak attractive dipole-dipole interactions, and A will have the highest boiling point and highest melting point in this series of compounds.
Molecules B and C are alkanes. They can only form the weakest attractive dispersion interactions between their molecular surfaces. Due to its long-thin shape, B will have a greater surface area and can form more dispersion interactions than the rounder C. Therefore, B will have a higher boiling point and melting point than C.
Molecule A is ionic (it has charges). Therefore, it can form the strongest ion-ion interactions and will have the highest boiling point and melting point.
Molecule B is a carboxylic acid with an acidic proton and basic lone pairs. Therefore, it can form medium strength hydrogen bonding interactions, and it will have the next highest boiling point and melting point.
Molecule C is a carboxylic ester, which is a polar functional group. However, it does not have an acidic proton. Therefore, esters cannot form hydrogen bonds with themselves. Instead, they can only form weak dipole-dipole interactions and will have the lowest boiling point and melting point in this series of compounds.
Answer:
Explanation:
By thinking about non covalent intermolecular interactions, we can also predict relative melting points. All of the same principles apply: stronger intermolecular interactions result in a higher melting point.
Which of the following materials would probably be used as a conductor of electric current in a computer chip?
A rubber
B. glass
c. plastic
D. gold
Answer:
gold is metal which is a very good conductor for electric current and most chips are made out of it.
Answer:
The answer is D. gold
Explanation:
which element requires the least i.e. potassium or gallium why
Answer:
Potassium
General Formulas and Concepts:
Chem
Reading a Periodic TablePeriodic TrendsIonization Energy - energy required to remove an electron from a given elementCoulomb's LawShielding EffectZ-effective and Forces of AttractionExplanation:
The Periodic Trend for 1st Ionization Energy is increasing up and to the right. That means He would have the highest I.E and therefore take the most amount of energy to remove an electron.
Potassium and Gallium are both in Period 4. Potassium is element 19 and Gallium is element 31.
Potassium's electron configuration is [Ne] 4s¹ and Gallium's electron configurations is [Ne] 4s²3d¹⁰4p¹. Since both are in Period 4, they have the same number of core e⁻. Therefore, the shielding effect is the same.
However, since Gallium is element 31, it has 31 protons compared to Potassium, which is element 19 and has 19 protons. Gallium would have a greater Zeff than Potassium as it has more protons. Therefore, the FOA between the electrons and nucleus of Ga is much stronger than that of K. Thus, Ga requires more energy to overcome those FOA to remove the 4p¹ e⁻. Since K has less protons, it will have a smaller Zeff and thus less FOA between the e⁻ and nucleus, requiring less energy to remove the 4s¹ e⁻.
is h2o+nacl a compound element or mixture
Answer:
H2O and NaCl are individual compounds. When NaCl is dissolved in H2O, a mixture is formed.
Explanation:
The chemical reaction for photosynthesis is: 6CO2 + 6H2O in sunlight yields C6H12O6 + 6O2. a. What is the function of sunlight in the reaction. b. What is the function of chlorophyll/ chloroplast?
Answer:
Sunlight provide light energy.
Chlorophyll absorb light.
Explanation:
Sunlight provide light energy or give light energy from sun and it is use to produce glucose from carbondioxide and water which is also a source of energy.
Chlorophyll absorbs light energy and use it to convert carbondioxide and water into glucose and oxygen or it captures sun rays and produce glucose and water.
A teacher showed this animal to students on a field trip which tool will allow the students to best see the animal up close
Answer:
Magnify glass
Which is heavier, calcium or selenium?
Answer:selenium
Explanation:
Answer: Nether
Explanation: Because if you have one pound of Calcium and one pound of selenium there both the same weight
Which of these types of changes is a physical change?
A. Breaking apart one substance into two substances
B. Dissolving one substance in another
C. Changing one substance into another
D. Making a new substance
Please helpppp i'll love you forever
The correct answer is A. Can I get the Brainliest?
When an aluminum atom becomes an ion, what is its charge?
Answer:
Initially, the aluminum atom had a charge of +13 + (−13) = 0; in other words, its charge was neutral due to the equal numbers of protons and electrons. When it becomes an ion, it loses 3 electrons, leaving behind only 10. Now the charge is +13 + (−10) = +3.
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Where else have you heard the term conservation? How does the term's meaning in that other context relate to its meaning in chemistry? please help me im so confuseddd
Answer:
See the answer below
Explanation:
Conservation is also a topic in Biology and it refers to the practice of managing natural resources - both living and non-living - with the aim of preserving them to secure the future of the human population.
Conservation in Chemistry refers to the property of chemical reactions in which no new matter or energy is created nor destroyed during the course of the reactions, although they can be converted from one form to another.
Conservation in Biology and Chemistry can be likened to each other based on the fact that both deal with preservation. While conservation in Biology focuses on how the ecosystem can be preserved, conservation in Chemistry deals with the preservation of matter/energy.
How do you determine if you have a covalent bond?
Answer:
If the electronegativity difference (usually called ΔEN) is less than 0.5, then the bond is nonpolar covalent. If the ΔEN is between 0.5 and 1.6, the bond is considered polar covalent. If the ΔEN is greater than 2.0, then the bond is ionic.
Explanation:
Hope this helped :)
Anita was using steel to make rusted sculptures. After building each sculpture, she caused the steel in the sculpture to rust by placing it into a tub filled
with salt water for eight hours. Anita wondered if steel would rust faster submerged in vinegar instead of salt water. To find out, Anita cut ten squares of
steel sheet metal and split them into two equal groups. She put one group of squares into a tub filled with salt water and the other group of squares
into a tub filled with vinegar. Once an hour for eight hours, Anita counted the number of rusted steel squares in each group.
What is the manipulated independent variable in Anita's experiment?
Answer:
The type of liquid in the tub (salt water or vinegar)
Explanation:
The manipulated independent variable in Anita's experiment is the type of liquid in the tub.
The independent variable is the controlled or manipulated variable in the course of an experiment. It can also be referred to as the 'cause' variable which has the capacity to produce 'effects' on another variable - the dependent variable.
In this case, the type of liquid the tub is filled (salt water or vinegar) will hypothetically affect the rusting period of the steel. Hence, the dependent variable is the type of liquid the tub is filled while the dependent variable would be the time it takes for the steel to get rusted.
What type of clothing would you need to wear if you could visit the mesosphere
The type of clothe that you would wear when visiting the mesosphere are the winter clothes.
What is mesosphere?Mesosphere is used to describe the coldest part of the earth whose temperature is -85°C.
An individual that wants to visit such a cold area should wear clothes that would provide such with warmth such as the winter clothes.
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GIVING BRAINLYYY
Use the general trends of the periodic table to answer the following question.
Platinum (Pt) and gold (Au) are sometimes called noble metals because they are less reactive than other metals. Based on this evidence and the periodic table, which other element is likely to be less reactive?
According to the electronic configuration, along with platinum and gold silver is considered to be a noble metal.
What is electronic configuration?
Electronic configuration is defined as the distribution of electrons which are present in an atom or molecule in atomic or molecular orbitals.It describes how each electron moves independently in an orbital.
Knowledge of electronic configuration is necessary for understanding the structure of periodic table.It helps in understanding the chemical properties of elements.
Elements undergo chemical reactions in order to achieve stability. Main group elements obey the octet rule in their electronic configuration while the transition elements follow the 18 electron rule. Noble elements have valence shell complete in ground state and hence are said to be stable.
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how can animal fossils help us understand the earth
Answer:
Some animals and plant are only known to us as fossils. hope this helps. and have a nice day:)
gasoline is separated from crude oil by heating it until it reaches it's boiling point. which separation method is used?
Answer:
Fractional distillation
Explanation:
The separation of gasoline from crude oil by heating until it reaches its boiling point is a separation technique called fractional distillation.
It is the separation of a mixture, such as crude oil into their respective fractions. This is achieved due to the differences in boiling point between the constituent fractions in the mixture. As the boiling point of a fraction is reached, it distills out from the column.