Answer:
Sodium.
Explanation:
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the periodic table. Its only stable isotope is ²³Na.
Answer:
sodium
atomic mass 22.99
atomic number 11
period 3 group 1 1a
sodium is also an Alkali metal
Explanation:
I have a periodic table on my computer I hope I helped
WHICH STATEMENT BEST REPRESENTS A HYPOTHESIS
Answer:
D
Explanation:
Hypotheses are educated guesses, and the best answer is the one with an if, as it indicates that it's a guess.
Answer:
letter b should be the answer
What type of Nuclear decay is shown by the reaction below
Answer:
bete is your answer.
have a great day.
I think c ....is write answers
Why does the battery give a reading of 9V even though there are no electrons flowing around the circuit?
Answer:
because battery have it's own voltage in it's composition
A reaction happens quickest during:
A. The beginning of the reaction
B. It is constant throughout the reaction
C. The end of the reaction
D. The middle of the reaction
The reaction is the formation of the product from the reactants. A reaction happens quickest during the beginning of the reaction. Thus, option A is correct.
What are the factors affecting the reaction rate?The reaction rate is the pace at which the reaction takes place and the breakdown or the combination of the reactants to produce the products. The rate of reaction depends on the concentration of the reactants.
The concentration of the reactants is in direct proportion with the rate as at the beginning of a reaction there is a higher amount of substance present than at the end.
As the reaction proceeds, the reactants get consumed and their concentration decreases. As there is a decrease in concentration the rate of the reaction converting and producing the products also decreases.
Therefore, option. the rate of reaction is fast at the beginning.
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what are the defects of mendeleev's periodic table
Answer:
1 Anomalous Pairs. The rest of the pairs of elements don't follow the follow Mendeleev's Principles . they are :
2Grouping of chemically dissimilar elements.
3Position of Isotopes.
4Electronic arrangement.
5Separation of chemically similar elements.
6The position of hydrogen.
Did you know that before pencil erasers were added on in 1858. people got rid of pencil markings
with white breadcrumbs? Which would erase pencil markings better, an eraser or white bread
crumbs?
Make a hyphotesis plz
Answer:
I guess eraser is better than bread crumbs
Erasers would be better than white bread or crumbs to erase the pencil marks because they would not leave any food marks on the paper and using bread crumbs.
What is an eraser?An eraser is an object of stationary which is used to remove pencil marks from the paper. It is used during writing, when we write something wrong, we could erase or remove the writing from the paper. It is very useful for small children because they usually make mistakes while studying.
Erasers are made from the milk of rubber plants. The milk is collected from the plants, and then it is mixed with chemicals and set down, and then cut into pieces.
Thus, Erasers would be preferable to utilizing bread crumbs or white bread because they would not leave any food stains on the paper after erasing the pencil markings.
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What is known about a reaction with a negative enthalpy?
A. The reaction is endothermic,
B. The reaction is spontaneous,
C. The reaction is exothermic,
D. The reverse reaction is favored,
Considering the definition of enthalpy of reaction, the correct answer is option C. a reaction with a negative enthalpy indicates that the reaction is exothermic.
Definition of enthalpy of reactionThe enthalpy of a chemical reaction as the heat absorbed or released when chemicals are transformed into a chemical reaction and it occurs at constant pressure.
The enthalpy is an extensive property, that is, it depends on the amount of matter present.
Finally, it must be taken into account that:
A reaction is called exothermic if its enthalpy of reaction is negative (that is, if the system gives up heat).A reaction is called endothermic if its enthalpy of reaction is positive (that is, if the system absorbs heat).SummaryIn summary, a reaction with a negative enthalpy indicates that the reaction is exothermic.
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En una carrera de atletismo un deportista se muestra agotado sin fuerzas para continuar y decide abandonar la carrera ¿Que alimentos tomo antes de la carrera ?
Answer:
Los alimentos para evitar la fatiga durante una carrera son alimentos bajos en grasas y altos en carbohidratos, así como alimentos bajos en fibra como pan, mantequilla de maní, plátano, jugo de frutas sin pulpa, y beber hasta aproximadamente 600 ml de líquido aproximadamente 3 horas. antes de la carrera
La comida para comer unos días antes de la carrera incluye carnes magras, arroz, pasta y verduras con contenido de almidón.
Los alimentos que se deben evitar incluyen carne roja, alimentos con alto contenido de grasas saturadas, alimentos fritos, pasteles y salchichas.
Explanation:
precautive measures taken when using pooter
I guess ensuring that you don't suck the insects or specimen collected by ensuring there is a net in the pooter
The process of diffusion can be described as: Movement of water from the area of high concentration of solute to the area of low concentration of solute. Movement of solute from the area of low concentration of solute to the area of high concentration of solute. Movement of water from the area of low concentration of solute to the area of high concentration of solute. Movement of solute from the area of high concentration of solute to the area of low concentration of solute.
Answer:
Movement of water from the area of high concentration of solute to the area of low concentration of solute.
Explanation:
Diffusion can be defined as the movement of gas molecules from a region of high concentration to a region of lower concentration until an equilibrium is attained or reached. This mixing of gas molecules in the liquid or gaseous state is due to their kinetic energy of random motion i.e without requiring bulk motion.
This ultimately implies that, diffusion is a phenomenon through which gas molecules in either a gaseous or liquid state spread out in response to a concentration gradient, which is simply the difference in concentration of the gases across a space.
During diffusion, molecules move from areas of high concentration to areas of low concentration. Also, diffusion does not require energy to move molecules.
Hence, the process of diffusion can be described as movement of water from the area of high concentration of solute to the area of low concentration of solute.
A solute can be defined as a substance that is typically dissolved in a liquid solvent such as water, coffee, tea, etc., to produce a solution.
which best describes nuclear energy?
A the energy that matter has due to the vibrations of its particles
B the energy an object has due to its chemical bonds
C the energy generated by a flow of electrons
D the energy stored inside the center of an atom
Answer:
The correct answer is - D. the energy stored inside the center of an atom.
Explanation:
Each atom has a small center in it called the nucleus and the energy that holds the nucleus or center of the atom together in the atom is known as nuclear energy.
It is the energy that is stored in the center of the atom and normally does not come out, however, in some radioactive atoms the sends some part of the energy as radiation.
Thus, the correct answer is - D. the energy stored inside the center of an atom.
how is electrovalent bond formed ? Describe with an example .
Answer:
For example, the bond between the sodium and chlorine atoms in sodium chloride (NaCl) is formed by the transfer of an electron from sodium to chlorine, creating Na + and Cl – ions. ... The electrostatic attraction between these ions provides the bonding in NaCl.
7. In a remote area of Columbia, kids have to travel to school on a zip-line!
Would school attendance increase if all kids has to get to school on a fun
zip line?
Make a hyphotesis
Help plz!!!
Answer:
yes
Explanation:
Kids like fun things, and school is not fun , so if kids got to go to school on a zipline, attendance would be through the roof!
In a synthesis experiment you obtain a sample of product on which you do a melting point determination and find a melting point range of 114 to 125 degrees Celsius. The sample is supposed to be acetylsalicyclic acid. What preliminary conclusion(s) can you reach from this one determination
Answer:
The melting point determination may need improvement- it may not have been done properly, and make sure it was repeated at least once.
Explanation:
Given that we know the actual melting point of pure acetylsalicyclic acid to be 135°, it follows that the process followed to obtain the melting point range of 114 to 125 degrees Celsius must be inaccurate.
Therefore, we can conclude that, the melting point determination may need improvement. It may not have been done properly, and we must make sure it is repeated at least once.
Name one diatomic compound which is mononuclei
Answer:
Common diatomic molecules include hydrogen (H2), nitrogen (N2), oxygen (O2), and carbon monoxide (CO). Seven elements exist as homonuclear diatomic molecules at room temperature: H2, N2, O2, F2, Cl2, Br2, and I2. The bond in a homonuclear diatomic molecule is non-polar due to the electronegativity difference of zero.
What name is given to a metal when it forms an ion, and what type of charge does it have?
Answer:
Cation metal. Positive charge.
Answer:
DHS has been working hard for years and it is still unclear whether this would happen if it is to end the market with the engine is a little less than the next 5years to be 8years in the first quarter and the same year in a quarter or less than a quarter or more than that
Energy in the amount of 420 J is added to a 35 g sample of water at a temperature of 10°C. What is the final temperature of the water?
The final temperature of the water, T2 = 38.57°C
Temperature can be defined as a measure of the degree of hotness or coldness of a physical object (body). Thus, it is measured with a thermometer and its units are degree Celsius (°C), Fahrenheit (°F) and Kelvin (°K).
A calorie refers to the amount of heat required to raise the temperature of a gram of water by one (1) degree Celsius (1°C).
Given the following data:
Quantity of energy = 420JMass = 35 gramsInitial temperature, T1 = 10°CThe specific heat capacity of water is 4.2 J/g°C.
To find the final temperature of the water (T2):
Mathematically, the quantity of energy (heat capacity) is given by the formula;
[tex]Q = mcdt[/tex]
Where;
Q represents the heat capacity or quantity of heat.M represents the mass of an object.C represents the specific heat capacity of water.dt represents the change in temperature.Substituting the values into the formula, we have;
[tex]420 = 3.5 \; * \; 4.2 \; * \; dt[/tex]
[tex]420 = 14.7 \; * \; dt\\\\dt = \frac{420}{14.7}[/tex]
Change in temperature, dt = 28.57°C
Next, we would solve for the final temperature by using this formula;
[tex]dt = T2 - T1[/tex]
[tex]28.57 = T_{2} - 10\\\\T_{2} = 28.57 \; + \; 10\\\\T_{2} = 38.57[/tex]
Final temperature, T2 = 38.57°C
Therefore, the final temperature of the water, T2 is equal to 38.57°C
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which of the following two conditions will favor a spontaneous reaction?
a) an increase in entropy and a decrease in enthalpy
b) an increase in both entropy and in enthalpy
c) a decrease in entropy and a decrease in enthalpy
d) a decrease in entropy and an increase in enthalpy
Two metals with equal mass will absorb heat according to their heat absorbing capacity.
The increase in entropy will cause the solid substance to break into multiple pieces.
When these solute particles detach from each other they will form a solution. Entropy increase will cause the temperature to increase.
Decrease in enthalpy is an exothermic reaction which releases heat from the reaction and then desired products will be formed.
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Câu 6: Cho 4,2 gam este đơn chức no E tác dụng hết với dung dịch KOH ta thu được 4,76
gam muối natri. Vậy công thức cấu tạo của E có thể là:
what is plasma in chemistry
Explanation:
Plasma is an ionized gas, a distinct fourth state of matter. “Ionized” means that at least one electron is not bound to an atom or molecule, converting the atoms or molecules into positively charged ions.but plasma is present in human body too in a liquid form.
hope this helps you
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Arrange the steps in order to describe how photons and carbon dioxide (CO2) contribute to the warming of Earth.
CO2 in the atmosphere absorbs infrared
photons.
CO2 in the atmosphere emits infrared photons back toward Earth.
Photons from the Sun strike Earth and become infrared photons.
Earth radiates infrared photons into the atmosphere
The Sun radiates sunlight (visible)
photons
The Sun radiates sunlight (visible) photons
Photons from the Sun strike Earth and become infrared photons.
Earth radiates infrared photons into the atmosphere
CO2 in the atmosphere absorbs infrared photons.
CO2 in the atmosphere emits infrared photons back toward Earth.
Certain gases are known to contribute towards global warming. Such gases are called greenhouse gases. The infrared rays from the sun are absorbed by these gases as they are re-emitted from the earth and re-emitted.
The sun radiates photons to the earth which is re-radiated into outerspace from the earth's surface. CO2 and other greenhouse gases absorbs these gases and re-emit them to the earth thereby causing a gradually rise in the temperature of the earth called global warming.
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what is the requirements to obtain citizenship?
please answer it correctly
Answer:
Age. ...
Residency. ...
Residence and Physical Presence.
Good Moral Character.
Attachment to the Constitution.
Language.
U.S. Government and History Knowledge.
Oath of Allegiance.
These are some requirements for obtaining citizenship .
Matty told Harriet that, later that same day, he was going to try to convince her to change her attitude toward the nutritional merits of doughnuts. Based on research findings regarding persuasion, how effective is Matty's strategy?
Answer:
The correct answer is - not very effective; forewarning tends to reduce the effectiveness of an attitude change
Explanation:
The strategy of forewarning or warning before attempting any change in the psychology of an individual is found to be less effective. The subject sees a forewarning seen as a warning that a person is going to attempt to make changes in the attitude of a person about a particular thing or situation.
As a result, the person is ready to defenses up with regard to that idea of persuasion which Builds up defenses for the situation. Therefore, the effect of persuasion is reduced on the person.
Thus, Matty's strategy is not very effective; forewarning tends to reduce the effectiveness of an attitude change
Assertion (A): An orbital cannot have more than two electrons, moreover, if an orbital has two electrons they must have opposite spins.
Reason (R): No two electrons in an atom can have the same set of all the four quantum
numbers.
a) Both A and R are true and R is the correct explanation of A.
b) Both A and R are true but R is not the correct explanation of A.
c) A is true but R is false.
d) Both A and R are false.
pls answer
Answer:
the correct answer is option ( A )
Both A and R are true and R is the correct explanation of A.
Explanation:
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If an atom has three shell and number of valence electrons are two. Is this element metal
or non-metal and why? Name the element and it’s valency.
Answer:
Metal
Element: Calcium
Valency: 2
Explanation:
To find the element, let's use the periodic table. (Look below)
We already went past 3 shells, just need the 2 electrons after it.
Just skip to the 4th row and count 2 to the right
We end up at Calcium.
Calcium is a metal and we're also on the alkaline earth metals column.
Calcium will need to lose 2 electrons to reach stability, so the valency is 2.
What is the chemical formula for carbon tetrafluoride?
The Periodic Table
1
mono-
2
di-
3
4
tetra-
5
penta-
hexa-
6
7
hepta-
8
Oct-
9
nano-
10
deca-
H3C6H507 + H2O + H3O+ + H2C6H507
acid
base
Explanation:
an acid will give away a proton and become a conjugate base.
A base will accept a proton and become a conjugate acid.
Convert 15,000 seconds into minutes
Answer:
250 minutes
Explanation:
60 seconds = 1 minute
15000 secods = 15000 / 60
1500 secons = 250 minutes
define SI unit system
Answer:
The SI base units are the standard units of measurement defined by the International System of Units (SI) for the seven base quantities of what is now known as the International System of Quantities: they are notably a basic set from which all other SI units can be derived.
A student wants to separate a mixture of salt and water in a laboratory (a) Describe how the student can obtain both salt and water from the salt solution
Answer:
okay so basically what you are being tested is if you know the difference between simple and fractional distillation and okay you can evaporate the mixture but you won't obtain water so you will use simple distillation to obtain both salt and water
