What does a pH of 7 say about a solution?
O A. The solution is at equilibrium.
B. The solution is neutral.
O C. The solution is acidic.
O D. The solution is basic.
Answer:
Its's B
The Solution is neutral
Explanation:
What information does the percent composition of an atom in a molecule
give?
A. The relative number of atoms one element contributes to a
molecule
B. The relative amount of mass an atom contributes to a molecule
C. The total mass that element contributes to a molecule
D. The total number of atoms of that element in a molecule
C.
This is basically the definition of percent composition which is how much mass a element contributes to a specific molecule.
Answer: B.
Explanation:
the relative amount of mass an atom contributes to a molecule
A chemist sets up a chemical reaction but finds that none of the reactant molecules have the required activation energy. What is the result?
A.
Products will form with less energy input.
B.
No products will be formed.
C.
The products will form too quickly.
D.
Products will convert to reactants.
Answer:
B.
No products will be formed.
What is the mass of the block of iron that has 10 cm 5 cm and 2 centimeters
Answer:
787.4g
Explanation:
The dimensions of the iron block is given as follows;
L = 10cm, B = 5cm, H = 2cm
Volume = L × B × H
Volume = 10 × 5 × 2
Volume = 100cm³
Density of iron metal = 7.874 g/cm³
Using the formula;
Density = mass/volume
Mass = density × volume
Mass = 7.874 × 100
Mass of iron = 787.4g
Research about the factors that influence the climates of these places including effects of Sun on the climate. Please give me fast i need help
Answer:
Distance from the sea, ocean currents, direction of prevailing winds, shape of the land, latitude, temperature, air pressure and distance from the equator.
Explanation:
Distance from the sea, ocean currents, direction of prevailing winds, shape of the land, latitude, temperature, air pressure and distance from the equator are the factors that influence the climates of any region. These factors has a great impact on the climate of a region, those regions which are nearer to the equator experiences hot climate whereas those regions which are far from the equator having cold climatic conditions.
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Give the structural formula of CH3CH(CH3)CH3
In the structure, we essentially have a Carbon with 3 methyl groups and a hydrogen attached to it
4.1 shows a plant cell. g For Examiner's Use n. C D Fig. 4.1 (i) Name the type of plant cell shown in Fig. 4.1. [1]
Answer:
palisade cell due to presence of chloroplasts
3. A typical peanut butter and jelly sandwich contains 360 kcal, of which 160
kcal comes from fat. Given 1 kcal = 4.2 kJ, how many J of fat would there be
in one PB&J sandwich?
Explanation:
here's the answer to your question
When 120 g of carbon reacts completely with 320 g of oxygen the mass of carbon dioxide formed will be?
Freezing point depression is:
A. When a substance freezes and then quickly drops in temperature.
B. When a substance drops in temperature until it freezes, then quickly rises in temperature but stays frozen.
C. When a substance does not need to be as cold as normal in order to freeze.
D. When a substance must be colder than normal in order to freeze.
Freezing point depression is when a substance must be colder than normal in order to freeze.
Freezing point is that temperature where a liquid substance becomes a solid i.e. freezes. Freezing point depression is the process whereby the temperature at which a substance freezes is lowered.Freezing point depression often occurs when a solute is added to a solvent. This reduces its freezing point. Since temperature is reduced, in other words, this means that the substance must become colder than normal for it to start freezing.
Hence, freezing point depression is when a substance must be colder than normal in order to freeze.
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D. When a substance must be colder than normal in order to freeze.
Explanation:
hey love, I just took the quiz on this for founder's education. I hope this helped.
The graph shows the volume of a gaseous product formed during two trials of a reaction. A different concentration of reactant was used during each trial, whereas the other factors were kept constant.
A graph is shown with two graph lines sloping upwards. The title on the x axis is Time and the title on the y axis is Amount of Product. The graph line with a steeper slope is labeled Trial X and the other is labeled Trial Y.
Which of the following statements explains which trial has a lower concentration of the reactant? (5 points)
Trial X, because the final volume of product formed is lower than Trial Y.
Trial X, because this reaction was initially fast and later stopped completely.
Trial Y, because the reaction was initially slow and later stopped completely.
Trial Y, because the volume of product formed per unit time is lower than Trial X.
Answer:
Trial Y, because the volume of product per unit time is lower than Trial X
Explanation:
In the chemistry experimental setup, the amount of gaseous product formed by the different concentration of the trials are measured and the result is plotted on a graph
The given graph, shows;
The vertical, y-axis = The amount of product
The horizontal, x-axis = Th time of the reaction
Trial X = The graph line with a steeper slope
Trial Y = The graph line
Increase in the concentration f the reactants, increases the number of collisions, and therefore, the number of effective collisions that gives the product also increases, and the overall rate of reaction increases
A more concentrated reactants produce more product in a shorter time (yield more product in less time) than a less concentrated one, and a more concentrated reactant would have a steeper slope and therefore produce more volume of the product in less time than a less concentrated reactant, which produces a lower volume in the same time
Therefore, the trial that has a lower concentration of the reactant is Trial Y, because the volume of product per unit time is lower than Trial X.
Answer:
There ya go
Explanation:
9. Which is true of a radioisotope that is used to date rock formations?
Answer:
Radiometric dating or radioactive date is the method that uses radioisotope to date the formation of a rock. The age of the rocks will be determined.
Explanation:
Radioactive deterioration is a natural process and results from the unstable atomic core, which releases bits and parts.
These radioactive particles are released as (there are many types). This decline process results in a more equilibrated nucleus, which makes the atom stable when the number of protons and neutrons balances.
This radioactivity is suitable for dating, as a radioactive "parent" item is constantly decaying into a stable "daughter" element.
A single mineral grain or a whole rock may be dated. There are techniques by which the sample is excited in a nuclear reactor and then measured with a mass spectrometer. The isotope (such as in the argon-argon scheme).
Others put mineral grains under a special microscope, fir in the grains with an ionising laser beam that releases the mineral and the isotopes.
The isotopes are measured by a mass spectrometer inside the same machine (an example of this is SIMS analysis).
Convert the following moles to grams :)
1. 2.4 moles sulfur
2. 1.5 moles BeI2
3. 7.5 moles C6H12O6
Answer:
3
Explanation:
sky is high and I am good.
How many moles of air are in a hot- air balloon with a volume of 2200m ^ 3 at a temperature of 388 K and a pressure of 100 kPa?
Answer:
Number of moles, n = 68.20 moles
Explanation:
Given the following data;
Volume, V = 2200 m³Temperature, T = 388 KPressure, P = 100 kPaIdeal gas constant, R = 8.314 J/mol·K or 0.08206 L·atm·mol−1·K−1To find the number of moles, we would use the ideal gas law equation;
PV = nRT
Where;
P is the pressure.V is the volume.n is the number of moles of substance.R is the ideal gas constant.T is the temperature.Making n the subject of formula, we have;
[tex] n = \frac {PV}{RT} [/tex]
Substituting into the formula, we have;
[tex] n = \frac {100 * 2200}{8.314 * 388} [/tex]
[tex] n = \frac {220000}{3225.832} [/tex]
Number of moles, n = 68.20 moles
Tenemos una disolución de HNO3 cuya pureza es del 65% y tiene una densidad de 1.32 g/mL. ¿Cuál es la molaridad de la disolución? PM HNO3 = 63.0 g/mol.
Teniendo en cuenta que la molaridad es el número de moles de soluto que están disueltos en un determinado volumen, la molaridad de la disolución de HNO₃ es 14.67 [tex]\frac{mol}{L}[/tex].
El porcentaje en masa o en peso de una disolución es el número de gramos de soluto que hay por cada 100 gramos de disolución.
Entonces una pureza de 65% indica que hay 70 g de HNO₃ puro por cada 100 g de HNO₃ impuro.
Por otro lado, la densidad es la relación entre el peso o masa de una sustancia y el volumen que ocupa esa misma sustancia.
Entonces, si la disolución de HNO₃ tiene una densidad de 1.32 g/mL (equivalente a 1320 g/L), donde la cantidad de masa es impura, se puede obtener la cantidad de masa de HNO₃ presente 1 L de la solución mediante el siguiente cálculo:
[tex]\frac{1320 g HNO_{3} impuro}{1 L}x \frac{70 g HNO_{3}puro}{100 g HNO_{3}impuro}= 924 \frac{g HNO_{3}puro}{L}[/tex]
Finalmente, la masa molar de HNO₃, es decir la masa presente en un mol de la sustancia, es 63 [tex]\frac{g}{mol}[/tex].
Entonces, teniendo en cuenta que la molaridad es el número de moles de soluto que están disueltos en un determinado volumen, es posible determinar la molaridad como:
[tex]\frac{924 g HNO_{3}puro}{L}* \frac{1 mol}{63 g}= 14.67 \frac{mol}{L}[/tex]
En resumen, la molaridad de la disolución es 14.67 [tex]\frac{mol}{L}[/tex]
Aprende más sobre la molaridad:
https://brainly.com/question/17647411?referrer=searchResultshttps://brainly.com/question/21276846?referrer=searchResultsI need help with question 2
Answer:
here's the answer to your question
Describe all the types of chemical reactions with example.
why can't sodium salt be prepared by double decomposition
Sodium salt might not be prepared by double decomposition because the method is used in preparing insoluble salts.
What is Double decomposition method?Double decomposition method serves as the method that is used in preparing compounds which entails reaction between two soluble compounds and after reaction soluble and insoluble products are produced.
Therefore, since most of the sodium salt are soluble salt , Double decomposition cannot be used to prepare them.
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What is said to have happened to the electrons in an atom in its ground state absorbs a quantum of energy from light
Answer:
The electron from the ground state to occupy a next energy level. In this case,we say that the electron is excited
How many chlorine (CI) atoms are in Methylene?
Answer:
None
Explanation:
Methylene is an organic compound and organic compounds consist of hydrogen atoms and Carbon atoms in n this case Methylene(CH2) has one carbon and two hydrogens .
Answer: methylene doesn't contain CL(chlorine) atoms
Explanation: the chemical formulae for Methylene is CH2
which means it contains only carbon and hydrogen atoms which is 1(one) carbon 2(two)hydrogen atoms
HOPE THIS HELPS!!
Identify the group number and generic outer electron configuration for a neutral main‑group element with the following two Lewis dot symbols.
X with 1 dot on the top, bottom and right
X with 1 dot on all sides
Answer: Answer to #1 is 3A and ns2np1
Answer to #2 is 4A and ns2np2
Explanation:Group number is the number of valance electrons and generic outer electron configuration has to add up to equal the number of valance electrons
The element in the first diagram is in group 13 while the element in the second diagram is in group 14.
The Lewis structure of an atom of an element is a representation of the number of valence electrons on the outermost shell of the atom of that element. Every group of elements have a generic electron configuration which represents the number of valence electrons contained by atoms of elements in that group.
In the first diagram, the element X belongs to group 3A(13) and has a generic outer electron configuration, ns2np1. In the second diagram, the element X is in group 4A(14) and has outer electron configuration ns2np2.
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how can we separate the sugar from sugar solution
which elements total number of electrons is equal to the number of core electrons in barium(Ba)?
Answer:
Xenon
Explanation:
The core electrons of an element are the electrons that do not take part in the chemical reactions of the element
The electronic configuration of barium Ba is presented as follows;
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s²
2+2+6+2+6+2+10+6+2+10+6
The valence electrons of boron are the 6s² electrons
The core electrons of boron are the; 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶
The electronic configuration of xenon, Xe, which is the previous noble element before barium, is presented as follows;
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ which is the same as the core electrons of barium
Therefore, the total number of electrons in xenon is equal to the number of core electrons in barium
Which of the following describes metallic character on the periodic table? Question 1 options: A) It increases as you move right to left within a period and down a group on the periodic table. B) It increases as you move left to right within a period and down a group on the periodic table. C) It increases as you move left to right within a period and up a group on the periodic table. D) It increases as you move right to left within a period and up a group on the periodic table.
Answer:
D
Explanation:
Metallic character decreases as you move across a period in the periodic table from left to right. This occurs as atoms more readily accept electrons to fill a valence shell than lose them to remove the unfilled shell. Metallic character increases as you move down an element group in the periodic table. This is because electrons become easier to lose as the atomic radius increases, where there is less attraction between the nucleus and the valence electrons because of the increased distance between them.
What are you most likely to observe when an endothermic reaction is taking place?
Answer:
An endothermic reaction is when heat is needed by the reaction, so it draws heat from its surroundings, making them feel cold. Just like a ice pack.
Calculate the amount of mole(s) of CoF2 required to react with 12.8 moles of HCI.
CoCl2 + 2HF --> CoF2 + 2HCI
Explanation:
here's the answer to your question
describe the different system of measurement
Answer:
A system of measurement is a collection of units of measurement and rules relating them to each other. ... Systems of measurement in use include the International System of Units (SI), the modern form of the metric system, the British imperial system, and the United States customary system.
Explanation:
Hope it works!!!!
Answer:
Systems of measurement in use include the International System of Units (SI), the modern form of the metric system, the British imperial system, and the United States customary system.
Please help I have been stuck on this problem for a couple hours and can't figure it out
Answer:
11.92 Liters O₂(g) at STP
Explanation:
For most stoichiometry problems, if one will convert all given data into moles, solve by rxn ratios, then finish by converting to needed dimensions to complete problem.
2Pb(NO₃)₂ => 2PbO + 4NO₂ + O₂
Given 237.5 grams PbO formed in reaction = 237.5 g/223.2 g/mole = 1.064 mole PbO
From equation ratios, moles O₂ formed = 1/2(moles PbO) = 1/2(1.064 moles O₂) = 0.532 mole O₂
0.532 mole O₂ = 0.532 mole x 22.4 liters/mole at STP = 11.91756272 liters (calculator answer) ≅ 11.92 liters O₂ at STP (4 sig.figs. based on given 237.5g PbO)
How the amount of acid rain caused by the burning of fossil fuels can be reduced ?
Answer:
The amount of acid rain caused by the burning of fossil fuels can be reduced by creating nitrogen oxides in the process of burning coal and other fossil fuels, some power plants are changing the way they burn coal. A great way to reduce acid rain is to produce energy without using fossil fuels. Instead, people can use renewable energy sources, such as solar and wind power.
2. A photon of wavelength for 4 x10 -7 m strikes on the metal surface the work
function of the metal being 2.13 eV.Calculate (i)the energy of the photon in
eV(ii) the kinetic energy of the emission(iii) velocity of the photoelectron
[1ev=1.602x10-19 J]
Answer:
See explanation
Explanation:
Energy of the photon;
E = hc/λ
h= Planks constant
c= speed of light
λ = wavelength
E= 6.6 × 10^-34 × 3 × 10^8/4 x10 -7
E = 4.95 × 10^-19 J
If 1ev=1.602x10-19 J
x = 4.95 × 10^-19 J
x= 3.1 ev
From Einstein's photoelectric equation;
KE = E - Wo
Where;
KE = kinetic energy of ejected photoelectron
E= energy of the photon
Wo= work function of the metal
KE = 3.1 eV - 2.13 eV
KE= 0.97 eV
KE = 0.97 eV × 1.602x10-19 J
KE = 1.55 × 10^-19 J
KE = 1/2 mv^2
1.55 × 10^-19= 1/2 × 9.1 × 10^-31 × v^2
v= √2 × 1.55 × 10^-19/9.1 × 10^-31
v= 5.8 × 10^5 m/s
