Answer:
the protection one
Explanation:
the cell wall acts a barrier
Ms. Sharkey wanted to see which tennis shoes made her run the fastest. She bought
a pair of Brooks, Adidas, and Nike and ran a mile in each to see which one gave her
the shortest time and recorded the data. What is her next step?
Answer:
to compare the data she has got?
Metal atoms always form a cation of a single, specific charge.
a.) True, because metal atoms form ionic compounds of a known composition.
b.) False, because some metal atoms are known to have more than one possible positive charge.
c.) True, because nonmetal atoms always form anions of a single, specific charge.
d.) True, because metal atoms lose all of their valence electrons.
e.) False, because elements in different rows of the periodic table can form different cations.
Answer:
c.) true, because nonmetal atoms always form anions of a single , specific charge
What has more
mass, a mole of
sodium chloride
or 2 moles of
aluminum?
Answer:
2 moles of aluminum
Explanation:
Group of molecules which do not contain carbon
O enzymes
O inorganic compounds
O buffer
O elements
what is the volume occupied by 6.022 X 10*23molecules of any gas at STP.
ZnO
Express your answer as an ion?
Answer:
[tex]Zn^{2+}[/tex]
Explanation:
Hello,
In this case, since metals tend to lose electrons, they usually become the cations when chemical compounds are formed so the other element should be negative to allow their interactions to take place.
In such a way, since oxygen is known to be negatively charged as -2 and their subscripts are both 1, we infer that the oxidation state of zinc is +2, therefore, it is written as an ion as follows:
[tex]Zn^{2+}[/tex]
Best regards.
Humans breathe about 500 mL of air per breath and take about 12 breaths per minute during normal activities. If a person is exposed to an atmosphere containing benzene at a concentration of 10 ppm (by volume), how many grams of benzene will be deposited in the lungs during an 8-hour shift if all the benzene that enters remains in the lungs
Answer:
mass of benzene in the lungs = 28.8 g of benzene
Explanation:
Volume of air breathed per hour = 500 mL * 12 * 60 = 360000 ml = 360 Litres of air
In 8 hours, volume of breathed air = 360 L * 8 = 2880 Litres of air
Concentration of benzene in air = 10 ppm
Note: 1 ppm = 1 mg per liter (mg/L)
10 ppm = 10 mg/L
Therefore, mass of benzene in the lungs in an 8-hour shift = 10 mg/L * 2880 L
mass of benzene in the lungs = 28800 mg
Converting to grams = 28800/1000
mass of benzene in the lungs = 28.8 g of benzene
The noble gas electron configuration for Ca2+ ion is identical with:______.
A. Ne.
B. Kr.
C. Ca.
D. Ar.
Answer:
D. Ar.
Explanation:
The electron configuration of the atom reflects how the electrons are distributed among the various atomic orbitals. Just as for neutral atoms, we use the Pauli exclusion principle and Hund’s rule in writing the ground-state electron configurations of cations and anions.
Ions formed from atoms of most representative elements have the noble-gas outer electron configuration of ns²np⁶. In the formation of a cation from the atom of a representative element, one or more electrons are removed from the highest occupied n shell. The electron configuration of calcium and its ion is as follows:
Ca: [Ar]4s² Ca²⁺ : [Ar]
An open-topped tub is filled completely to the top edge with solid ice. What will happen when the ice melts?
A)
The tub will overflow.
B)
In the process of melting, 9 percent of the water will be converted to water vapor.
C)
The level of the water will be lower than the edge of the tub.
D)
There will be no change in the level of the tub.
Answer:
d
Explanation:
Answer:
B
Explanation:
Water that is heated move
PLS HELP !!!
Answer:
it moves faster when heated
Answer:
the answer is faster
Explanation:
why because water moves faster when heated
Is it possible for a diprotic acid to have Ka1?
Answer:
Yes, it is possible.
Explanation:
A diprotic acid is an acid that can release two protons. That's why it is called diprotic.
Monoprotic → Release one proton, for example Formic acid HCOOH
Triprotic → Releases three protons, for example H₃PO₄
Polyprotic → Release many protons, for example EDTA
it is a weak acid.
In the first equilibrum, it release proton, and the second is released in the second equilibrium. So the first equilibrium will have a Ka1
H₂A + H₂O ⇄ H₃O⁺ + HA⁻ Ka₁
HA⁻ + H₂O ⇄ H₃O⁺ + A⁻² Ka₂
The HA⁻ will work as an amphoterous because, it can be a base or an acid, according to this:
HA⁻ + H₂O ⇄ H₃O⁺ + A⁻² Ka₂
HA⁻ + H₂O ⇄ OH⁻ + H₂A Kb₂
Convert .0027 CL to mL.
Answer:
0.027 ml
Explanation:
[tex]1\:cl = 10\:ml\\0.0027 \: cl = x\:ml[/tex]
Cross Multiply
[tex]x = 0.027 \:ml[/tex]
During which change of state do atoms lose energy?
A. Sublimation
B. Freezing
C. Boiling
D. Melting
If you answer my question Thank You, If I don't thank you in time!
Determine the mass in grams of 2.98 × 10²¹ atoms of arsenc. Determine the mass in grams of 2.98 × 10²¹ atoms of arsenc.
Answer:
37.1 g of Arsenic
Explanation:
2.98 x 10^21 atoms of Arsenic x 74.92g/6.02 x 10^23
= 223.26 x 10^21/6.02 x 10^23
= 2.2326 x 10^23/6.02 x 10^23
= 37.1 g of Arsenic
I am timed please help
Answer:
compound
Explanation:
MgO is an inorganic compund :) The simplest explanation is that it's not an element b/c there's two elements (Mg & O) in the substance, and it's not a mixture b/c you can't easily separate the two elements.
Answer:
magnesium when magnesium is burnt by heat it forms an compound called magnesium oxide
Look at the list of wealthy Americans under the heading “Half a Billion Back of M'Kinley."
What were the two most common industries of the business leaders on
this list?
manufacturing and carpets
banking and railroads
o jewelry and transportation
Answer:
banking and railroads
Explanation:
The two most common industries of the business leaders on this list are banking and railroads.
What are industries?
Industry is a group of productive enterprises or organizations that produce or supply goods, services, or sources of income. In economics, industries are generally classified as primary, secondary, tertiary, and quaternary; secondary industries are further classified as heavy and light.
Primary industry sector of a nation’s economy includes agriculture, forestry, fishing, mining, quarrying, and the extraction of minerals. It may be divided into two categories: genetic industry, including the production of raw materials that may be increased by human intervention in the production process; and extractive industry, including the production of exhaustible raw materials that cannot be augmented through cultivation.
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how do you convert wavelength to frequency?
Answer:
Image result for how do you convert wavelength to frequency?
How do you calculate energy from wavelength?
Convert your wavelength into meters.
Divide the speed of light, ~300,000,000 m/s, by the wavelength in m. This gives you the wave's frequency.
Multiply the frequency by Planck's constant, 6.626 x 10-34. The result is the waves energy in joules (J).
Explanation:
Which statement best describes the polarity of SCL4F2?
a. The molecule is always polar.
b. The molecule s always nonpolar.
c. Depending on the arrangement of outer atoms, this molecule could be polar or nonpolar.
Answer: Depending on the arrangement of outer atoms, this molecule could be polar or nonpolar.
Explanation:
Polarity is when the electric charge that is leading to a molecule is being separated.
The polarity of SCL4F2 can either be polar or non polar and this depends on the arrangement of outer atoms. It is the arrangements of these outer atoms that'll help in the determination of its polarity.
The molecule SCl4F2 could be polar or nonpolar depending on the arrangement of outer atoms.
The molecule SCl4F2 could have different arrangements of outer atoms. That means that there are two possible arrangements of the molecule. Depending on which arrangement the outer Cl and F atoms have, the molecule cold be polar or nonpolar.
In the arrangement of SCl4F2 which could be polar is the one in which the dipoles in the molecule do not cancel out. In the other arrangement, the dipoles cancel out and the molecule is nonpolar.
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An atom with a mass number of 27 has 14 neutrons. What element is the atom?
Answer:
aluminum i think
Explanation:
2-An analysis that establishes the chemical identity of the species
A)Quantitative Analysis
B) Quantitative Synthesis
C)Qualitative Analysis
D)Qualitative Synthesis
Q1-(30 Marks) Choose the correct answer
Answer:
C Qualitative Analysis.
Explanation:
Rounding 6.42 g to 2 significant figures
Answer:
6.4
Explanation:
How do you find the average density?
Answer:
total mass divided by its total volume
Explanation:
if volume stays the same, what happens to pressure?
Answer:
Pressure will stay the same if volume stays the same.
Answer:
Volume is inversely proportional to pressure, meaning if one goes up the other goes down and vise-versa. With volume remaining the same and there are no other given factors, pressure also remains the same
What was Albert Einstein's contribution to our understanding of the
photoelectric effect?
A. He described the relationship between energy and mass.
B. He described photons as little packets of electrons.
C. He described electricity as moving electrons.
D. He described light as little packets called photons.
Answer: The Answer Is D, He described light as little packets called photons.
Explanation:
The contribution of Albert Einstein to our understanding of the photoelectric effect is he described light as little packets called photons. The correct option is D.
Who is Albert Einstein?The theory of relativity, which Albert Einstein developed and is rightfully famous for, transformed our understanding of space, time, gravity, and the cosmos.
Along with his work on relativity, the physicist established the scientific principles behind items like paper towels, lasers, and other everyday items.
Since Einstein first suggested using the use of light quanta to clarify the photoelectric impact, quantum theory accurately portrays the photoelectric impact. The quantum theory of radiation gives this concept a formal formulation.
Therefore, the correct option is D. He described light as little packets called photons.
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A 4.00 (±0.01) mL Class A transfer pipet is used to transfer 4.00 mL of a 0.302 (±0.004) M Cu2+ stock solution to a 100.00 (±0.08) Class A volumetric flask. Deionized water is used to bring the flask to volume. Calculate the concentration of the diluted soluion in the volumetric flask and report its absolute uncertainty.
Answer:
concentration of diluted solution = 0.0125 ( ± 0.0002)M
Uncertainty = ± 0.0002
Explanation:
Given that
Initial volume of Cu2+ = 4.00 (±0.01) mL
Initial molarity 0f Cu2+ = 0.302 (±0.004) M
transferred to 100.00 (±0.08) Class A volumetric flask
first we get amount of water added
100.00 (±0.08) - 4.00 (±0.01) = 96 ± (0.09)
Now according to law of dilution
The concentration of Cu2+ after adding water
M1V1 = M2V2
we substitute
0.302 (±0.004) * 4.00 (±0.01) = x * 96 ± (0.09)
Now the multiplication of two digits with uncertainty is
(0.004/0.302) * 100 = 1.32% ; (0.01/4.00) * 100 = 0.25%
= [0.302 ( ± 1.32% )] * [ 4.00 ± (0.25%)]
= 1.208 ±(1.57%)
1.57/100 * 1.208 = 0.0189
so
= (1.208 ± 0.0189)
now substitute in our previous equation
1.208 ± (0.0189) = x * 96 ± (0.09)
x = 1.208 ± (0.0189) / 96 ± (0.09)
{ 0.09/96 * 100 = 0.094% }
so x = 1.208 ± (1.57%) / 96 ± (0.094% )
x = 0.0125 ± ( 1.664)
now( 1.664/100 * 0.0125)
= ± 0.000208
Hence
concentration of diluted solution = 0.0125 ( ± 0.0002)M
Uncertainty = ± 0.0002
Which of the following experimental methods cannot be used to measure the rate of a reaction? Group of answer choices measurement of the absorbance of a colored reactant with time measurement of the change in the partial pressure of a gas-phase product over time measurement of the equilibrium concentration of an acidic product via titration with a strong base measurement of the absorbance of a colored product with time measurement of the change in the partial pressure of a gas-phase reactant over time
Answer:
measurement of the equilibrium concentration of an acidic product via titration with a strong base
Explanation:
The rate at which a reaction proceeds refers to how quickly the reaction is occuring. In other words, it is how quickly the reactants are changing to the products. According to the question, the rate of a reaction can be measured experimentally using the reactants' or products' properties e.g volume, pressure etc.
Since reactions must involve reactants and products, the manner in which either the reactants or products changes over time can be measured. For example; measurement of the absorbance of a colored reactant or product with time, measurement of the change in the partial pressure of a gas-phase reactant or product over time can be used.
However, a measurement of the equilibrium concentration of an acidic product via titration with a strong base will not tell us how fast the reaction is going because it is in an EQUILIBRIUM state i.e. reaction is occuring at an equal rate
any help with these questions would help i'm lost
Answer:
1. 31.25 mL
2. 1.98 g/L
3. 0.45 g/mL
Explanation:
For each of the problems, you need to perform unit conversions. You need to use the information given to you to convert to a specific unit.
1. You need volume (mL). You have density (g/mL) and mass (g). Divide mass by density. You will cancel out mL and be left with g.
(50.0 g)/(1.60 g/mL) = 31.25 mL
2. You are given grams and liters. You need to find density with units g/L. This means that you have to divide grams by liters.
(0.891 g)/(0.450 L) = 1.98 g/L
3. You have to find density again but this time with units g/mL. Divide the given mass by the volume.
(10.0 g)/(22.0 mL) = 0.45 g/mL
Draw the line-bond structure of oleic acid (cis-9-octadecenoic acid), CH3(CH2)7CH=CH(CH2)7COOH, at physiological pH. You do not need to draw hydrogen atoms attached to carbon atoms.
Answer:
Explanation:
Oleic acid originates from an unsaturated fatty acid with 18 carbon atoms and one double bond, which can be found in olive oil and many other vegetable and animal oils and fats. Its economic importance includes the production of soap making and cosmetics etc.
The line-bond structure of the given oleic acid in the question can be found in the attached below.
The line-bond structure of oleic acid is given in the image attached. The line-bond structure represents the number of carbon atoms.
Oleic acid:Oleic acid is an omega-9 fatty acid. It can be made by the body. It is also found in foods. Highest levels are found in olive oil and other edible oils. Oleic acid is most commonly used for preventing heart disease and reducing cholesterol. It is long chain of 18 Carbon atoms.
It is found in oils such as olive, palm, peanut, and sunflower.
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Calculate the time,speed is 100m/s and distance is 2000 meter
Explanation:
Time = Distnace ×speed
so distance is 2000m
and speed is 100
so 100×2000
time = 200000s
What are the steps to solving: 0.8102m x 3.44m
Answer:
2.787088m^2
Explanation:
well you multiply both numbers and then since its multiplication you can add both variables and there two
The steps for solving: 0.8102m x 3.44m is given below in explanation part, and the answer for this is [tex]2.788088m^2[/tex].
To begin solving the 0.8102m multiplied by 3.44m multiplication issue, multiply the numerical numbers together: 0.8102 x 3.44 = 2.788088.
Then add the units together: m x m = [tex]m^2[/tex]. Finally, add the numerical value and unit to get the following result: 2.788088 [tex]m^2[/tex].
We are multiplying two measures by metres (m) in this computation. When we multiply the numerical values, we get the product, and when we multiply the units, we get the final unit, which in this case is metres squared ( [tex]m^2[/tex]).
Thus, this signifies that the multiplication reflects a computation of area. The final value, 2.788088 [tex]m^2[/tex], is the product of multiplying the two measures supplied.
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