Answer: Yes you are.
Explanation:
A deep teeth cleaning can remove a buildup of plaque and tartar on your teeth, reducing gum inflammation and improving gum health. Plaque is a sticky film that forms on teeth. It contains bacteria and develops when food particles mix with saliva. You can remove plaque, which collects on teeth daily, by brushing your teeth.
Name
12. A chemist places a piece of solid magnesium in an aqueous solution of copper (II)
sulfate and notices a reaction. Pieces of solid copper dropped out of the solution as a
precipitate and magnesium sulfate was formed.
a) Give a balanced formula equation (with state symbols) for this reaction (3 marks)
Answer:
Explanation: Mg(s) + CuSO4 (aq) -> Cu(s) + MgSO4 (aq)
Sulfuric acid reacts with aluminum hydroxide by double replacement producing aluminum sulfate and water Write chemical reaction. If 30 g of sulfuric acid reacts with 25 g of aluminum hydroxide, identify the limiting reactant?
Answer: [tex]H_2SO_4[/tex] is the limiting reagent.
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
The balanced chemical equation is:
[tex]3H_2SO_4(aq)+2Al(OH)_3(aq)\rightarrow Al_2(SO_4)_3(aq)+6H_2O(l)[/tex]
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} H_2SO_4 =\frac{30g}{98g/mol}=0.31moles[/tex]
[tex]\text{Moles of} Al(OH)_3=\frac{25g}{78g/mol}=0.32moles[/tex]
According to stoichiometry :
3 moles of [tex]H_2SO_4[/tex] require = 2 moles of [tex]Al(OH)_3[/tex]
Thus 0.31 moles of [tex]H_2SO_4[/tex] will require=[tex]\frac{2}{3}\times 0.31=0.21moles[/tex] of [tex]Al(OH)_3[/tex]
Thus [tex]H_2SO_4[/tex] is the limiting reagent as it limits the formation of product and [tex]Al(OH)_3[/tex] is the excess reagent.
Height
O
Genetic
O Environmental
O Both
Answer:
its both because your hight can change if u do exercises
Hope it helped.
is copper an elementary substance or a compound?
Calcium carbonate decomposes into
calcium oxide and carbon dioxide.
The mass of calcium carbonate that
decomposes is 57 g. At the end of
the experiment, the mass of the
products were only 45 g. What can
we conclude from this information?
Answer:
The mass of carbon dioxide formed is 12g.
A beaker contains a sample of water with a mass of 325 grams. The water in the beaker
is boiled and weighed again after it cools. The new mass of the water is 305 grams. In
this example of the conservation of matter in physical changes,
A. the mass is less after it cools because water has less mass as a gas.
B. the mass of the water was 305 grams and the mass of the water vapor was 20 grams.
C. the process of boiling destroyed 20 grams of the water and left 305 grams of water.
D. the heat energy created by boiling water makes up the rest of the mass.
Answer: a
Explanation:
Bc I just did it and yeah
Which of the following have London dispersion forces?
a. methane
b. carbon tetrachloride
c. bromine trifluoride
d. all of the above
Which is an example of a chemical change?
A. heating a block of ice to form liquid water
B. heating a tungsten wire until it glows brightly
C. adding sugar crystals to water to form a clear, colorless liquid
D. passing an electric current through water to form hydrogen and oxygen
Answer:
D. passing an electric current through water to form hydrogen and oxygen
Explanation:
only one that's not just a physical change.
how many moles of solute are present in a 2 L of a 25M potassium nitrate solution
a. 0.5 moles
b. 2 moles
c. 50 moles
d. 25 moles
I NEED THIS ANSWER ASAP, im taking the quiz right now and i need HELPPP
Answer:
50 moles
Explanation:
took the quiz
Can someone please help me with the right answer? I only have one more attempt :(
Can someone double check my work? (Ideal Gas Law Equation)
I am solving for the amount of moles in two gases.
For one, it was 4.75mL at 0.5C (273.65K) and 1.2atm.
n=(1.2*4.75)/(0.0821/273.65)=(5.7/22.456)=0.25361653 moles
For the other gas, it was 4.6mL at 0.5C and 1.2atm.
n=(1.2*4.6)/(0.0821/273.65)=(5.52/22.456)=0.24581403 moles
Please double check these for any errors in math or whatever. Thank you.
I did not see any errors, i may be wrong but what i can see is that it is correct
4. A girl walked for 30 minutes. She noticed that she traveled farther in the first 15 minutes of
her walk than in the second 15 minutes,
What can she conclude about her walk?
A she walked over many hills
B
her average speed was faster during the first part of her walk
C. she walked in two different directions
D. she was walking at a constant speed
During the chemical reaction given below 21.71 grams of each reagent were allowed to react. Determine how many grams of the excess reagent are left over after the reaction is complete. 2SO2()+O2()⟶2SO3()
Answer: 16.32 g of [tex]O_2[/tex] as excess reagent are left.
Explanation:
To calculate the moles :
[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]
[tex]\text{Moles of} SO_2=\frac{21.71g}{64g/mol}=0.34mol[/tex]
[tex]\text{Moles of} O_2=\frac{21.71g}{32g/mol}=0.68mol[/tex]
[tex]2SO_2(g)+O_2(g)\rightarrow 2SO_3(g)[/tex]
According to stoichiometry :
2 moles of [tex]SO_2[/tex] require = 1 mole of [tex]O_2[/tex]
Thus 0.34 moles of [tex]SO_2[/tex] will require=[tex]\frac{1}{2}\times 0.34=0.17moles[/tex] of [tex]O_2[/tex]
Thus [tex]SO_2[/tex] is the limiting reagent as it limits the formation of product and [tex]O_2[/tex] is the excess reagent.
Moles of [tex]O_2[/tex] left = (0.68-0.17) mol = 0.51 mol
Mass of [tex]O_2=moles\times {\text {Molar mass}}=0.51moles\times 32g/mol=16.32g[/tex]
Thus 16.32 g of [tex]O_2[/tex] as excess reagent are left.
Which body system includes the lungs?m
Answer: The respiratory system
Explanation: It includes the nose, mouth, throat, voice box, windpipe, and lungs. Air enters the respiratory system through the nose or the mouth.
What element is found in water?
1. Carbohydrate
2. Carbon
3. oxygen
Explanation:
3. the element is oxygen
NH₄⁺(aq)+NO₃⁻(aq) → NH₄NO₃(s)
How much energy is released when 3 moles of NH₄+ react?
1) -25.69 kJ
2) -51.38 kJ
3) -77.07 kJ
4) -102.76 kJ
Colin decided to investigate soil erosion by water. He measured rates of erosion on
model hills made of soil, rock, and sand. Which of the following was the test
(independent) variable?
Answer:
i just had a test on this with 2 attempts and got it wrong on both but i do know that the answer is not...
the steepness of the models hillside
or
the rate of erosion on the hills
so the answer is either...
the amount of water sprayed on the hills
or
the type of material used to construct the model hills
but i think its the amount of water sprayed on the hills...i hope i helped a lil ;)
Explanation:
Please help :)
It’s a science thing for 7th grade
Answer: The first question is chemical The second one is Physical
Explanation:
Determine from the balanced chemical reaction if
the derived mole ratio is correct or incorrect.
2FeBr3 + 3Na2S → Fe2S3 + 6NaBr
2 moles FeBra
3 moles Na2S
Answer:
Correct
Explanation:
According to the balanced chemical reaction, 2 mol FeBr3 are consumed for every 3 mol Na2S consumed.
A balanced equation obey the law of conservation of mass. The coefficients are the numbers which are added to balance the chemical equation. Here the given mole ratio is correct.
What is a balanced equation?An equation in which the number of atoms of reactants and products on both sides of the equation are balanced is defined as the balanced chemical equation. The coefficients which are added in front of the formula of each component represents the number of the species.
A molar ratio denotes the ratio between the amounts in moles of any two compounds involved in a balanced chemical reaction. By comparing the coefficient of each component, the mole ratio can be determined.
Here for the given reaction, for every 3 moles of Na₂S consumption 2 moles of FeBr₃ is also consumed. So the molar ratio of Na₂S to FeBr₃ is 2/3. Molar ratios are used as the conversion factors between products and reactants in many chemistry problems.
To know more about mole ratio, visit;
https://brainly.com/question/29095152
#SPJ7
Enrichment of nuclear fuel 2 points A. increases the relative concentration of uranium-235 to 3-20% to produce energy in a power plant. B. increases the relative concentration of uranium-235 to 30-50% to avoid a nuclear explosion at higher percentages. C. increases the relative concentration of uranium-235 from 60% to 90% to achieve maximum electricity generation D. decreases the relative concentration of uranium-235 from 100% to 30-50% to avoid a nuclear explosion at higher percentages.
Answer:
B. increases the relative concentration of uranium-235 to 30-50% to avoid a nuclear explosion at higher percentages.
Explanation:
Uranium enrichment may be defined as a process which is necessary for creating effective nuclear fuel from the mined uranium by mainly increasing the percentage of the uranium-235 that undergoes fission with a thermal neutrons.
The enrichment process removes the unwanted uranium-238, thus making uranium 235 concentration higher. It takes up much work to increase the relative concentration of the uranium 235 to make it 30% to 50% so as to avoid a nuclear explosion at such higher percentages.
PLEASE HELP WITH CHEM !! Calculate the [OH-] of each of the following solutions given the [H+]. AND Classify each of the solutions in the question above as either acid, base, or neutral. AND FIND THE PH
pH, pOH, [H+], and [OH-] are all interrelated. For simplicity, we assume that we're working with aqueous solutions at 25 °C.
The following mathematical relations are relevant here:
pH = -log[H⁺]pOH = -log[OH⁻][H⁺] = 10^-pH[OH⁻] = 10^-pOHpH + pOH = 14[H⁺] × [OH⁻] = 10^-14A pH of 7 is neutral; a pH less than 7 is acidic; and a pH greater than 7 is basic.
---
We are given four solutions of varying [H⁺], and we want to find the pH and the [OH⁻]. The pH will tell us whether the solution is neutral, an acid, or a base.
Finding the [OH⁻]Using the relationship [H⁺] × [OH⁻] = 10^-14, we can calculate the [OH⁻] of each solution by dividing 10^-14 by the given [H⁺]:
[OH⁻] = 10^-14/(3.3 × 10^-5) = 3.0 × 10^-10
[OH⁻] = 10^-14/(4.0 × 10^-8) = 2.5 × 10^-7
[OH⁻] = 10^-14/(7.2 × 10^-11) = 1.4 × 10^-4
[OH⁻] = 10^-14/(8.2 × 10^-4) = 1.2 × 10^-11
Note: While not indicated here, the units for [H⁺] and [OH⁻] are moles/liter (M).
Finding the pHTo find the pH of each solution, we take the negative logarithm of the [H⁺] with base 10, i.e., pH = -log₁₀[H⁺]:
pH = -log(3.3 × 10^-5) = 4.48
pH = -log(4.0 × 10^-8) = 7.40
pH = -log(7.2 × 10^-11) = 10.14
pH = -log(8.2 × 10^-4) = 3.09
Note that, for significant figures involving logarithms, the number of decimal places should equal the number of significant figures in the argument of our logarithm (the argument is what we're taking the -log of). Since we're taking the -log of quantities given to two significant figures, our corresponding pH values are given to two decimal places.
Acid, Base, or Neutral?As mentioned above, a pH = 7 is neutral, a pH < 7 is acidic, and a pH > 7 is basic.
4.48 < 7, so the first solution is an acid.
7.40 > 7, so the second solution is a base.
10.14 > 7, so the third solution is a base.
3.09 < 7, so the fourth solution is an acid.
in pressure dunt
uwing
frost shattering
Answer:
i dont get it???????
Explanation:
the process plants use to make sugar for food
A respiration
B eqidermis tissue
C photosynothedis
D chlorophyll
object with a mass of 30 kg is observed to accelerate at the rate of 4 m/s2. Calculate the force required
Lunar Eclipse. Choose ALL that apply
Question 1 options:
Earth casts its shadow on the moon
The moon turns dark
Light from the sun is blocked
Earth is directly between the moon and sun
Question 2 (0.5 points)
Solar Eclipse: Choose ALL that apply
Question 2 options:
The Earth is directly between the moon and sun
Earth casts a shadow on the moon
Moon moves between the sun and Earth
The moon blocks out the light of the sun and casts a shadow onto the Earth
In this exercise we have to use the knowledge of lunar eclipse to identify the alternatives that correspond to this effect, as follows:
Light from the sun is blockedEarth is directly between the moon and sunWhat is lunar eclipse?A lunar eclipse happens when the Earth is between the Moon and the Sun, at times when they are aligned. Depending on the position of the Moon, it is total, partial or penumbral. Different stages of a lunar eclipse on a full moon night.
Now, use the knowledge of solar eclipse to identify the alternatives that correspond to this effect, as follows:
Moon moves between the sun and EarthThe moon blocks out the light of the sun and casts a shadow onto the EarthWhat is the definition of solar eclipse?Solar eclipse is an astronomical phenomenon that occurs when the Moon is positioned between the Earth and the Sun, hiding the light emitted by the star towards the planet.
See more about eclipse at brainly.com/question/25105283
What happens to pressure if temperature increases? Pressure increases. Pressure stays the same. Pressure decreases. Temperature has no effect on pressure.
Answer:
Pressure increases
Explanation:
According to Gay-Lussac's law, the pressure of a given amount of gas is directly proportional to the temperature at a given volume i.e.
[tex]P\propto T[/tex]
It means the relationship between the pressure and the temperature is direct.
If the temperature increases, the pressure of the gas also increases. Hence, the correct option is (A).
1. When _____
are added or removed from an atom, _____
is formed
Answer:
1.) protons or electrons 2.) ion
Explanation:
is it true or false?
Answer:
The rainforest is teeming with animals and insects, so you would hear humming. Frogs and birds make some of the loudest rainforest sounds.
howler monkeys, are the loudest so i think that its false cause lost of animals are there but some can be quiet
What is a mole of something? Why do scientists use the concept of a mole?
Answer: A mole is a chemical unit to measure mass of substance.
Explanation:
A mole can be defined as 6.02214076 × 1023 of atoms, ions, molecules and others. A mole is the total amount of discrete entity within a substance present in the form of atoms, ions, and molecules. As atoms, ions, molecules are small entities within any substance so it is necessary to measure each of them and recognize them so the scientists development the concept of mole. It is the convenient unit of measurement because of the presence of greater number of molecules, atoms, and ions present in any substance.
Answer:
The mole is an SI unit used to measure the amount of any substance. One mole is exactly 6.02214076×10 23 particles.
Explanation:
The concept of the mole is important for scientists because it means that one mole of any element has exactly the same number of atoms as one mole of any other element. This information allows chemists to count atomic particles for even very complex chemistry formulas and reactions.
what is the mass number for an atom that has 36 protons 36 electrons and 40 neutrons
Answer:
76
Explanation:
Mass number = number of protons plus the number of neutrons
So, 36 + 40 = 76