Nearsightedness or myopia is a condition where the person can see the near objects clearly but distant objects appears blurred. This eye condition is corrected with contact lenses or prescription eyeglasses. Another approach is LASIK or corrective eye surgery. In LASIK laser is used to correct the vision.
According to Charles Law, if you have a balloon inside a car at noon during a hot summer day the balloon molecules inside will increase in pressure.
A. true
B. false
Final answer:
The claim that a balloon's internal pressure increases due to Charles's Law on a hot day is false; Charles's Law relates gas volume to temperature at constant pressure, meaning the balloon's volume would increase, not pressure.
Explanation:
The statement that balloon molecules inside a balloon will increase in pressure on a hot summer day according to Charles's Law is false. Charles's Law actually states that the volume of a given amount of gas is directly proportional to its temperature on the Kelvin scale when the pressure is held constant. When the temperature inside the car increases, the gas molecules inside the balloon move faster and if the balloon is elastic and can expand, the volume of the gas will increase while the pressure inside the balloon will not necessarily increase if it is free to expand.
I'LL GIVE U BRAINLIEST
Which should be done in case of a laboratory accident? Check all that apply.
a)Stay calm.
b)Read directions completely.
c)Do not try to clean up a spill.
d)Follow the teacher’s directions.
e)Wear appropriate lab attire.
f)Leave the area.
Answer : The correct options are, (a), (c), (d) and (f).
Explanation :
There are some safety rules for science lab when we are performing the experiments :
Always wear the lab coat to protect you from chemicals. Always wear the gloves in your hands. Always wear the face mask to protect you from the pungent smell of chemicals. Always wear the glasses to protect the eyes. Before doing some experiment wash all the materials with distilled water.There are some safety rules for science lab in case of a laboratory accident:
Always stay calm at that time. Do not try to clean up a spill. Always follow the directions of the teacher. Leave the area immediately.Hence, the correct options are, (a), (c), (d) and (f).
A chemistry teacher adds 50.0 mL of 1.50 M H2SO4 solution to 200 mL of water. What is the concentration of the final solution? Use .
Answer:
option A
Explanation:
just took test on e2020
Soda is acidic, I need to know what kind of acid soda includes..
My options are:
1. Sulfuric acid - found in batteries and acid rain.
2. Acetic acid - found in vinegar.
3. Citric acid - found in citrus fruits like lemons and limes.
4. Hydrochloric acid - found in stomach acid and many industrial applications.
Please help it’d mean a lot! <3
How many grams are in 1.68 x 1026 molecules of CO2? (molar mass=44.01 g/mol) (Hint: You will need to use your entire stoichiometry flow chart)
Answer:
There is [tex]12277.494g[/tex] of CO2
Explanation:
We know that the molar mass of CO2 is [tex]44.01\frac{g}{mol}[/tex]
This means that in 1 mole of molecules of CO2 is 44.01 g of CO2
In one mole of molecules of any substance there are N molecules where N is defined as the Avogadro number.
[tex]N=AvogadroNumber=(6.02214076).10^{23}[/tex]
Therefore, we can write that
In [tex](6.02214076).10^{23}[/tex] molecules of CO2 (1 mole of CO2) there is 44.01 g of CO2 ⇒
In [tex](1.68).10^{26}[/tex] molecules of CO2 there will be x grams :
[tex]x=\frac{(44.01).(1.68).10^{26}}{(6.02214076).10^{23}}g=12277.494g[/tex]
We answer that in [tex](1.68).10^{26}[/tex] molecules of CO2 there is [tex]12277.494g[/tex] of CO2
Which of the following statements is true?
A. Stars that appear to move very much are very far from earth
B. The more a star appears to move, the farther is it from earth
C. Stars that do not appear to move are very close to earth
D. The less a star appears to move, the farther it is from earth.
Answer:
The correct answer is option D. The less a star appears to move, the farther it is from earth.
Explanation:
Hi!
Let's solve this!
The stars, like the Earth move. We see them still as they are far away, the distance is very large. The stars we see in motion are the ones that are very close.
Then, the further a star is, the quieter we will see it.
After the analysis, we conclude that the correct answer is option D. The less a star appears to move, the farther it is from earth.
What happens to the shape of a liquid when you pour it into a container?
A system at equilibrium is placed under stress by adding more reactant. If this reaction has a small equilibrium constant (Keq), how will the addition of this stress affect the equilibrium of this system.
Question options:
The equilibrium will shift to produce more reactant.
The equilibrium will shift to produce more product.
There is no way to predict how the stress will affect this system without more information.
The reaction will generate more heat.
During the process of photosynthesis, plants use energy from the Sun to transform carbon dioxide from the air into A. minerals and liquid carbon dioxide. B. protein and minerals. C. oxygen gas and molecules of sugar.
Photosynthesis is the process through which plants make their own food.
Special structures called chloroplasts—located inside plant cells—help plants capture light energy from the Sun. The plants then use the energy to build molecules of sugar from carbon dioxide gas and water. Oxygen gas is a waste product of photosynthesis. Plants releases this waste oxygen into the air.
Which of the following are observations?
- The candle floats.
- The tires are flat.
- The dog is barking.
- The tire is flat because of a decrease in temperature.
- If a person walks by, then the dog will bark.
Describe two uses of surfactants
Answer:
if its on edge this is what it provides!
- Surfactants are used to help improve gas exchange in the lungs of premature infants.
- Surfactants are used to prevent salad dressings from separating.
- Pulmonary surfactants reduce the surface tension of the gas exchange surfaces in the lungs, allowing gases to diffuse more easily.
- Surfactants help the water molecules and oil molecules in salad dressings interact and mix.
Make sure to change up the answer a bit!
If you eat 3.00 moles of sugar, how many molecules did you consume?
3.00
2.00 x 10^23 molecules
5.00 x 10^ -24 molecules
1.81 x 10^24 molecules
What is the total number of neutrons in an atom of 0-18?
Answer: The number of neutrons in given isotope are 10
Explanation:
Atomic number is defined as the number of protons or electrons that are present in a neutral atom.
Atomic number = number of protons = number of electrons
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
The isotopic representation of an atom is: [tex]_Z^A\textrm{X}[/tex]
where,
Z = Atomic number of the atom
A = Mass number of the atom
X = Symbol of the atom
We are given:
An isotope having formula: [tex]_{8}^{18}\textrm{O}[/tex]
Atomic number = Number of protons = 8
Mass number = 18
Number of neutrons = 18 - 8 = 10
Hence, the number of neutrons in given isotope are 10
Write the balanced equation for the decomposition of hydrogen peroxide to form water and oxygen.
The balanced chemical equation for the decomposition of hydrogen peroxide into water and oxygen is 2 H2O2 (aq) → 2 H2O (l) + O2 (g).
Explanation:The student has asked for the balanced chemical equation for the decomposition of hydrogen peroxide (H2O2) into water (H2O) and oxygen gas (O2). The reaction can be represented as follows:
2 H2O2 (aq) → 2 H2O (l) + O2 (g)
Here, the hydrogen peroxide molecules are breaking down into water molecules and oxygen gas. The equation is balanced with four hydrogens and four oxygens on both sides; therefore, adhering to the law of conservation of matter.
half life worksheet answer key 1. How long does it take a 100.00g sample of As-81 to decay to 6.25g?
Answer:
132 seconds ( 2 Minutes 12 seconds).
Explanation:
Half life is basically the time it takes for a compound to decay to half of it's original mass.
In this problem, the compound is As. The half life of As-81 is 33 seconds. This means it takes 33 seconds for 100 g of As-81 to decay to 50g. The question however id to find the time it takes for it to decay to 6.25g.
We find how many half life's it would take,
100 --> 50 (First half life)
50 --> 25 (Second half life)
25 --> 12.5 (Third half life)
12.5 --> 6.25 (Fourth half life)
This means the total time is 4 * 33 (Half life) = 132 seconds ( 2 Minutes 12 seconds).
How many grams of nickel (+2) are required to replace all of the silver when 15.55 grams of AgNO3 are present?
2AgNO3 + Ni2+ = Ni(NO3)2 + 2Ag+
From the reaction, it can be seen that AgNO3 and Ni2+ has following amount of substance relationshep:
n(AgNO3):n(Ni)=2:1
From the relationshep we can determinate requred moles of Ni2+:
n(AgNO3)=m/M= 15.5/169.87=0.09 moles
So, n (Ni)=n(AgNO3)/2=0.045 moles
Finaly needed mass of Ni2+ is:
m(Ni2+)=nxM=0,045x58.7=2.64g
What is the oxidation state of each element in the species Mn(ClO4)3? I'm going over oxi-redox reactions from a long time ago and I'm trying to remember properly.
Mn=3+
Cl=7+
and oxygen=2- right?
How many milliliters of a 5.0 M H2SO4 stock solution would you need to prepare 108.0 mL of 0.45 M H2SO4?
To prepare 108.0 mL of a 0.45 M H2SO4 solution, you would need to measure 9.72 mL of the 5.0 M H2SO4 stock solution.
Explanation:To solve this problem, we can use the concept of dilution. The formula for dilution is C1V1 = C2V2, where C1 and V1 are the concentration and volume of the stock solution, and C2 and V2 are the concentration and volume of the diluted solution.
In this case, the given concentration of the stock solution is 5.0 M and the volume of the stock solution needed is unknown. The desired concentration of the diluted solution is 0.45 M and the volume of the diluted solution is 108.0 mL. Plugging in these values into the dilution formula will give us the volume of the stock solution needed.
Let's solve for V1:
(5.0 M)(V1) = (0.45 M)(108.0 mL)
V1 = (0.45 M)(108.0 mL)/(5.0 M)
V1 = 9.72 mL
Therefore, you would need to measure 9.72 mL of the 5.0 M H2SO4 stock solution to prepare 108.0 mL of 0.45 M H2SO4.
What is the ph of a solution with a hydroxyl ion (oh-) concentration of 10-10 m? what is the ph of a solution with a hydroxyl ion (oh-) concentration of 10-10 m? ph 10 ph 12 ph 4 ph 2?
The pH in chemistry has been defined as the "power of hydrogen" that specifies and estimates the acidity and basicity. The pH of the solution with a hydroxyl concentration of 10⁻¹⁰ is 4. Thus, option c is correct.
What is pH?pH has been defined as the "potential of hydrogen" that is used to define the specificity of the acid and alkaline behavior of the solution. It has been the measure of the hydrogen or the hydroxide ions concentration dissociated into the solution.
pH is calculated as:
pH = −log ([H⁺])
Given,
Hydroxide ion concentration = 10⁻¹⁰
The relation between pH and pOH is given as:
pOH = - log [OH⁻]
pH = 14 - pOH
pOH is calculated as:
pOH = - log [OH⁻]
pOH = - log [10⁻¹⁰]
pOH = 10
Substituting values in the formula for pH as:
pH = 14 - pOH
pH = 14 -10
= 4
Therefore, option c. the pH is 4.
Learn more about pH, here:
https://brainly.com/question/4884748
#SPJ2
Chemoautotrophs use ___ as an energy source and ___ as a carbon source. select one:
a. inorganic compounds: organic compounds
b. light: organic compounds
c. organic compounds: organic compounds
d. light: co2
e. inorganic compounds: co2
autotrophs are organisms that can synthesise organic compounds (e.g.: carbohydrates) from inorganic C compounds (e.g.: CO2)
Phototrophs are those use photons also known as light energy, chemotrophs are those who utilize chemical energy as their source of energy. chemotrophs can either use inorganic or organic molecules as source of energy. from the options given there are 2 answers with CO2, the correct combination is CO2 with inorganic compounds
Therefore chemoautotrophs use inorganic compounds as an energy source and CO2 as a carbon source
Which would you expect to experience a greater effective nuclear charge? which would you expect to experience a greater effective nuclear charge? a 2p electron of an atom a 3s electron of a na atom?
Answer:
A 2p electron of a Ne atom
Explanation:
Mastering chemistry
If two covalently bonded atoms are identical, the bond is
A pure covalent bond occurs when two identical atoms share electrons equally, resulting in a nonpolar covalent bond.
Explanation:A pure covalent bond occurs when two covalently bonded atoms are identical. In this type of bond, the electrons are shared equally between the two atoms, resulting in a nonpolar covalent bond. Nonpolar covalent bonds form between two atoms of the same element or between different elements that share electrons equally, such as molecular oxygen (O2).
Pure covalent bonds typically form in situations where the participating atoms are of the same element, such as in the case of molecular oxygen (O2), where two oxygen atoms share electrons equally. Understanding pure covalent bonds is essential in comprehending the nature of chemical bonding and the characteristics of various compounds.
Learn more about Covalent bonds here:https://brainly.com/question/16655971
#SPJ11
Which of the following is not an example of a scientific model?
Which has the lighter mass one mole of platinum or one mole of zirconium?
How many neutrons are in an atom of tin? Round your answer to the nearest whole number.
Answer: 69
Explanation:
As we know that the formula to find the no of neutrons= Atomic mass (A)- atomic number (Z)
No of neutrons (n)=A-Z
n=1189-50
n=69
which observation would be best evidence of carbon cycling?
A.) water droplets
B.)moving animals
C.)plant growth
D.) dead plants
Answer: C.)plant growth
Explanation:
The carbon cycling is a process in which the carbon and it's various organic forms are transformed and delivered to various earth spheres such as biosphere, geospheres, hydrospheres, pedospheres and atmosphere. Carbon is the basic element found in all life forms. The cycling of carbon can best be observed in the plant growth. This is because of the fact that carbon is obtained by the plants in the form of carbon dioxide which is a chief ingredient required for the process of photosynthesis. Photosynthesis is necessary for the plants to produce food in the form of carbohydrates required for the growth and metabolism in plants.
How many electrons does the predictable (most common) ion of calcium contain?
In the balanced redox reaction: 2 cu(s) + s(s) ® cu2s(s), how many electrons are gained or lost by each copper atom? select one:
a. each copper atom gains two (2) electrons.
b. each copper atom gains one (1) electron.
c. each copper atom loses one (1) electron.
d. each copper atom loses two (2) electrons.
Answer: Option (c) is the correct answer.
Explanation:
The given reaction equation is as follows.
[tex]2Cu(s) + S(s) \rightarrow Cu_{2}S(s)[/tex]
The oxidation-reduction half reactions will be as follows.
Oxidation : [tex]Cu(s) \rightarrow Cu^{+} + 1e^{-}[/tex]
Reduction: [tex]S(s) + 2e^{-} \rightarrow S^{2-} [/tex]
By balancing the above half reactions, oxidation-half reaction will be as follows.
[tex]2Cu(s) \rightarrow 2Cu^{+} + 2e^{-}[/tex]
Whereas reduction-half reaction will remain the same.
Hence, it shows that each copper atom is losing one electron to combine with a sulfur atom.
Therefore, we can conclude that each copper atom loses one (1) electron.
If 0.98 moles of BaCl2 are dissolved in enough water to make a 1.2-liter solution, what is the resulting molarity?
A. 0.55 M BaCl2
B. 0.82 M BaCl2
C. 1.2 M BaCl2
D. 0.45 M BaCl2
Which statement describes the Arrhenius interpretation of acids and bases
Answer:
It is limited to situations that involve aqueous solutions or specific compounds.
Explanation:
the answer was correct on edge