Answer:
The answer would be:
C. Potassium and magnesium
Explanation:
because the only have valence electrons
which best represents the number of moles in exactly 130 grams of potassium metal?
Answer:
if by EXACTLY means 130.0000, then the answer is 3.3250
by EXACTLY means 1.299 <Kmass<1.301 then the answer is 3.33
EXPLANATION
which best represents the number of moles in exactly 130 grams of potassium metal?
the elemental mass of K is 39.098
so exactly 130 divided by 39.098 = 3.3250
if by EXACTLY means 130.0000, then the solution is 3.3250 by EXACTLY means 1.299 <Kmass<1.301 is 3.33
What is Potassium Metal?
Potassium metal responds rapidly with atmospheric oxygen to create flaky white potassium peroxide in exclusively moments of exposure.
It stood preferably isolated from potash, the ashes of plants, from which its appellation derives.
In the systematic table, potassium is one of the alkali metals, all of which have a single valence electron in the outermost electron shell,
That is easily drawn to produce an ion with a positive charge a cation, that connects with anions to form salts. Potassium in disposition materializes only in ionic salts.
When the elementary mass of K is 39.098
Therefore, exactly 130 divided by 39.098 is = 3.3250
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How many moles is 78.0 grams of sodium?
Answer:3.39
Explanation:
The half-life of Palladium-100 is 4 days. After 16 days a sample of Palladium-100 has been reduced to a mass of 6 mg. What was the initial mass (in mg) of the sample
Answer:
96mg
Explanation:
Since the half-life of Palladium-100 is 4 days and the sample has been reduced after 16 days, that means the sample has undergone four half-lives. To find the intial mass, just work backwards:
6 x 2= 1212 x 2= 2424 x 2= 48 48 x 2= 96As you see, I've worked backwards from the four half-lives. So the initial mass after 16 days is 96 mg.
The measurable properties of a substance, such as vapor pressure and surface tension, occur due to the strength of
electrical forces between particles, as given by Coulomb's law
electrical forces between particles, as given by Newton's law
gravitational forces between particles, as given by Newton's law
O gravitational forces between particles, as given by Coulomb's law
Answer:
electrical forces between particles, as given by coulombs law.
Explanation:
Properties of a substance such as vapor pressure and surface tension depend on electrical forces between particles, as given by Coulomb's law.
The vapor pressure refers to how easily a liquid converts to gas while surface tension is the force that makes a liquid surface act as a stretched elastic skin.
Both vapor pressure and surface tension has a lot to do with the degree of polarity in a molecule. Usually, polar molecules have a low vapor pressure and high surface tension due to a high electrical forces between particles, as given by Coulomb's law.
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Determina la molaridad de una solución de H2S, si se colocaron 37 ml del ácido en 890 ml de solución. La densidad del H2S es de 1.36 g/ml
Por definición de molaridad y densidad, la molaridad de la solución es 1.66 [tex]\frac{moles}{litros}[/tex].
La concentración molar o molaridad es una medida de la concentración de un soluto en una disolución que indica el número de moles de soluto que están disueltos en un determinado volumen.
La molaridad de una solución se calcula dividiendo los moles del soluto por el volumen de la solución:
[tex]Molaridad=\frac{numero de moles de soluto}{volumen}[/tex]
La Molaridad se expresa en las unidades [tex]\frac{moles}{litros}[/tex].
Por otro lado, la densidad es una magnitud que permite medir la cantidad de masa que hay en determinado volumen de una sustancia.
Entonces, la expresión para el cálculo de la densidad es el cociente entre la masa de un cuerpo y el volumen que ocupa:
[tex]densidad=\frac{masa}{volumen}[/tex]
En este caso, siendo H₂S el soluto, se colocaron 37 ml del ácido, siendo su densidad 1.36 [tex]\frac{g}{mL}[/tex]. Reemplazando en la definición de densidad se obtiene:
[tex]1.36\frac{g}{mL}=\frac{masa}{37 mL}[/tex]
masa= 1.36 [tex]\frac{g}{mL}[/tex]× 37 mL
masa= 50.32 g
Siendo 34 g/mol la masa molar de H₂S, es decir la cantidad de masa que una sustancia contiene en un mol, la cantidad de moles de H₂S puede ser calculada como:
[tex]numero de moles de H_{2}S= 50.32 grams\frac{1 mole}{34 grams}[/tex]
número de moles de H₂S= 1.48 moles
Siendo 890 mL=0.890 L el volumen de la solución, entonces la molaridad puede ser calculada como:
[tex]Molaridad=\frac{1.48 moles}{0.890 L}[/tex]
Molaridad= 1.66 [tex]\frac{moles}{litros}[/tex]
Finalmente, la molaridad de la solución es 1.66 [tex]\frac{moles}{litros}[/tex].
Aprende más:
https://brainly.com/question/17647411?referrer=searchResultshttps://brainly.com/question/21276846?referrer=searchResultsHow do you find the frequency of a recorder?
Answer:
Modern recorders are most commonly pitched at A=440 Hz, but among serious amateurs and professionals, other pitch standards are often found. For the performance of baroque music, A=415 Hz is the de facto standard, while pre-Baroque music is often performed at A=440 Hz or A=466 Hz.
Explanation:
How many deciseconds are
in 554 seconds?
Give your answer in standard form.
Answer:
5540
Explanation:
Answer:
5,440
Explanation:
10 deciseconds = 1 seconds
554 seconds = 5,440 seconds
what is an environmental result from burning fossil fuels?
Answer:
Burning fossil fuels emits a number of air pollutants that are harmful to both the environment and public health. Sulfur dioxide (SO2) emissions ...
what type of bacteria use the enzyme nitrate reductase to metabolize nitrogen oxides and transform them back to nitrogen gas?
Denitrifying Bacteria such as Pseudomonas aeruginosa is the type of bacteria that use enzyme nitrate reductase to metabolise nitrogen oxides to nitrogen gas.
Denitrification is the process whereby nitrites or nitrogen oxides is converted to nitrogen gas by a denitrifying Bacteria such as Pseudomonas.
Pseudomonas aeruginosa uses enzyme nitrate reductase to reduce nitrate to nitrite.
Then nitrite is then converted back to nitrogen gas.
Therefore, Pseudomonas aeruginosa is a type of bacteria that uses enzyme nitrate reductase.
Does anyone know what the answer to the question is?
Answer:
rate = (6.48 M-1 • s-1)[Cl2O5]2
Explanation:
A sample of gas is at 78.0 oC. You want to change the volume of the gas from 1.60 L to 0.425 L under constant pressure. What must you do to the temperature of the gas
Answer:
the rule is V1/T1= V2/T2
so we convert the T1 from °c to kelvin
78+273.15= 351.15 k
1.60/351.15 = 0.425/T2
4.55 ×10-³ = 0.425/T2
then T2 = 93.40 kelvin
hence, we should decrease the temperature
asap help for brainlst
List the 7 diatomic elements in the periodic table.
Question 5 options:
All alkaline earth metals- Be, Mg, Ca, Sr, Ba,Ra.
All elements in the periodic table are diatoms.
H2, N2, O2,F2, Cl2, Br2, I2
All group 16 elements-O, S, Se, Te, Po.
Answer:
Group 2A (or IIA) of the periodic table are the alkaline earth metals: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). They are harder and less reactive than the alkali metals of Group 1A. The name comes from the fact that the oxides of these metals produced basic solutions when dissolved in water, and they remained solids at the temperatures available to the ancient alchemists. Like the Group 1A elements, the alkaline earth metals are too reactive to be found in nature in their elemental form.
The alkaline earth metals have two valence electrons in their highest-energy orbitals (ns2). They are smaller than the alkali metals of the same period, and therefore have higher ionization energies. In most cases, the alkaline earth metals are ionized to form a 2+ charge.
The alkaline earth metals have much higher melting points than the alkali metals: beryllium melts at 1287ºC, magnesium at 649ºC, calcium at 839ºC, strontium at 768ºC, barium at 727ºC, and radium at 700ºC. They are harder metals than the Group 1A elements, but are soft and lightweight compared to many of the transition metals.
Salts of the Group 2A metals are less soluble in water than those of Group 1A because of the higher charge densities on the 2+ cations; nevertheless, many Group 2A salts are at least moderately soluble. Some Group 2A salts bond strongly to water molecules, and crystallize as hydrates; among these are Epsom salt, MgSO4·7H2O, and gypsum, CaSO4·2H2O.
Explanation:
Answer:
H2, N2, O2, F2, Cl2, Br2, I2
Explanation:
The 7 diatomic elements in the periodic table are Hydrogen, Nitrogen, Oxygen, Fluorine, Chlorine, Bromine and Iodine.
what weighs more a gallon of water or a gallon of butane
Answer:
a gallon of water weighs more than a gallon of butane
Two chemical reactions are shown:
A. Ca(OH)2 - CaO + H2O
B. 4K + O2 + 2K20
Which statement is true?
A. Both are synthesis reactions
B. Both are decomposition reactions
C. A is a synthesis reaction, and B is a decomposition reaction
D. A is a decomposition reaction, and B is a synthesis reaction
Answer: A is a decomposition reaction, and B is a synthesis reaction
Explanation: the first equation shows the reactant breaking up into 2 parts aka decomposition and equation 2 shows the reaction being combined into one part, aka synthesis. hope that helps!
Answer:
Answer d
Explanation:
what is the periodic trend for electronegativity
Answer:
mark me brainlest
Explanation:
Electronegativity values generally increase from left to right across the periodic table. Electronegativities generally decrease from top to bottom of a group. The highest electronegativity value is for fluorine.
Answer:
"Electronegativity increases as you move from left to right across a period because the number of charges on the nucleus increases." (sstudy30 on Quizlet)
Explanation:
It explains itself haha!
Have a nice day!
I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)
- Heather
MULTIPLE CHOICE QUESTION
Which of the above represents a cell in an
isotonic solution?
B
А
C
Answer:
B
Explanation:
explain the factors that affect the separation of mixtures in amino acids
A student conducts an experiment to separate water into hydrogen and oxygen through a chemical reaction as shown below.
H Hydrogen gas Orygengu rises in this test tube test tube.
2 H2O --> 2H2 + O2
As a result the student collects 28.0 g of hydrogen and 224.0 g of oxygen. How many grams of water did the student originally start with?
The amount, in grams, of water, that the student originally started with would be 252 g
From the balanced equation of the reaction, the ratio of H2O to H2 is 1:1. Thus for every 1 mole of water that is separated, 1 mole of H2 is produced.
Recall that: mole = mass/molar mass
Mole of 28.0 g H2 produced = 28/2
= 14 moles
Equivalent mole of H2O would, therefore, be 14 moles.
Mass of 14 moles H2O = mole x molar mass
= 14 x 18
= 252 g
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complete the word equations below to show how the metals are extracted from their oxides: 1) tin oxide + carbon ---> .........? + .......? 2) lead oxide + carbon ----> ......? + ......?
Answer:
1.) Tin oxide + Carbon → Tin + Carbon monoxide.
2.) Lead oxide + Carbon → Lead + Carbon monoxide.
These equations show that the metals are being extracted by their oxides by heating with carbon. This is because the metals (Tin and Lead) are less reactive than carbon. Remember, extraction methods of metals are determined by their reactivity. Since the elements tin and lead are less reactive than carbon, the extraction process of heating with carbon is needed. Remember that when a metal heats with carbon, the carbon displaces the metal from the compound and removes the oxygen from the oxide. Leaving you with the metal and carbon monoxide.
What is the common name for N2O? mononitrogen dioxide dinitrogen monoxide nitrogen oxide nitrous oxide.
Considering the IUPAC name, the common name for N₂O is nitrous oxide
IUPAC (International Union of Pure and Applied Chemistry), is the recognized authority in the development of standards for the naming of chemical compounds, through their Interdivisional Commitee on Nomenclature and Symbols.
The IUPAC name to N₂O is nitrous oxide. Nitrous oxide is commonly known as the laughing gas is a colorless gas with a pleasant, sweetish odor and taste that, when breathed, causes placidity to pain.
Learn more:
https://brainly.com/question/25759961https://brainly.com/question/23036094?referrer=searchResultshttps://brainly.com/question/25759613Answer:
on e2020 the first one is dinitrogen monoxide second one is nitrous oxide
Explanation:
Rank the following molecules (1st, 2nd, 3rd, 4th) in the order that they melt.
Sucrose
Iodine
Sodium
Paraffin
There is a picture attached
Sodium chloride has the highest melting point while iodine has the least melting point.
The melting points of solid substances depends on the nature of intermolecular forces that exists in the substance. The stronger the magnitude of intermolecular forces in a substance, the higher its melting point.
The order of melting points of the solids shown in question is as follows;
1st - Sodium chloride2nd - sucrose3rd - paraffin4th - IodineSodium chloride has the highest melting points because it is an ionic substance. Among the molecular sucrose and paraffin, sucrose has a higher melting point than sucrose because it has a greater molar mass. Iodine, a molecular substance has the least molar mass and the least melting point in the list.
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Explain why some metals are extracted by heating their oxides with carbon, but some metals cannot be extracted in this way
Answer:
This happens because a metal is less reactive than carbon and it can be extracted from its oxides by heating with carbon. The carbon displaces metal from the compound and removes the oxygen from the oxide.
aldosterone plays a primary role in adjustment of ____________ excretion.
doy CORONITA a quien me ayude rapido que es un examen porfaaa
Answer:
thank you for the points
A student has a sample of ocean water that they take to science class. what steps could be taken to determine to classify the ocean water as a suspension, solution, element, or compound?
A) Examine the pH of the sample. If the pH is exactly neutral, it is a pure substance that is a compound.
B) Evaporate the water. If salt is left behind, the sample is a mixture that can be defined as a solution.
C) Let the sample settle. If the salt settles to the bottom, it is a mixture that is classified as a solution.
D) Observe the diffraction of light as it moved through the sample. If light does not scatter, it is a pure substance that is elemental.
Answer:
A or D because B and C dont make sense
How is heat transferred when a person holds a pen that is already at body
temperature?
A. From the hand to the pen
B. Heat is not transferred.
C. In both directions between the pen and the hand
D. From the pen to the hand
SUBMIT
Answer:
The answer is B.
Explanation:
Heat is not transferred.
1. Why fractional distillation has
fractionating column but not in simple
distillation?
Answer:
fractional distillation leads to better separation
los hermanos Ana Victoria y José Leonardo están patinando en el hielo, con 25 y 20 kg respectivamente de masa, si Victoria empuja a Leo y este sale despedido con una aceleración de 2 m/s²
calcula la aceleración con que retrocede la niña, suponiendo que los patines no ofrecen resistencia al movimiento
Utiliando las leyes de Newton encontraremos que la aceleración de Ana es -1.6 m/s^2.
La segunda ley de Newton dice que:
F = m*a
Fuerza es igual a masa por aceleración.
La tercera ley de Newton dice que cuando dos objetos interactuan, cadan objeto ejerce una fuerza de igual magnitud pero opuesta direccion en el otro.
Ahora veamos como aplicar esto.
Sabemos que la niña empuja al niño, asumamos que con una fuerza F.
Tendremos entonces la ecuación:
F = 20kg*(2m/s^2) = 40N
Y por la tercer ley de Newton, esta misma fuerza (pero en opuesta dirección) se aplica a la niña, entonces tendremos:
-40N = 25kg*a
-40N/25kg = a = -1.6 m/s²
La aceleración con la que retrosede la niña es -1.6 m/s²
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what is the ka for 0.03M Solution of HClO4 for 1.90 PH value.
A) 7.2x10^-3
B) 8.27x10^-3
C) 8.27x10^-4
D) 6.27x10^-4
(I keep getting 5x10^-3 when I round all the values to 2 decimal places but it’s not in the options)
Monica put four items on the desk that you need to measure the mass of. The items are listed below. Which of the following would need to be put in a container in order to measure the mass on a scale?
I. Flour
II. Sugar cubes
III. Milk
IV. An unbroken egg
A. I and III
B. I and IV
C. II and III
D. III and IV
Answer:
it D because it make more sense