Answer:
B. Dividing the number by 1,000
Explanation:
Every time you move the decimal ,add a zero.Since the decimal is moved three times ,there are three zeroes. When you move left ,the number is getting smaller so it is division.
Explain why this combination of compounds can or cannot make a buffer solution. Hint: apply definition of a buffer, mechanism of its action and consider whether the compound is acid (weak/strong) or base (weak/strong). HF (0.2 mol) and NaOH (0.1 mol)
Answer:
This combination can make a buffer
Explanation:
A buffer is defined as an aqueous mixture of a weak acid and its conjugate base, or vice versa.
In the problem, HF is a weak acid, and its conjugate base is F⁻.
When NaOH reacts with HF, F⁻, Na⁺ and H₂O are produced as follows:
NaOH + HF → F⁻ + Na⁺ + H₂O
As there are initially 0.2mol of HF and 0.1mol NaOH, after the reaction you will have:
0.1mol HF and 0.1mol F⁻. As both, the weak acic and the conjugate base are present:
This combination can make a bufferC. Balance these fossil-fuel combustion reactions. (1 point)
The question is incomplete. The complete question is :
C. Balance these fossil-fuel combustion reactions. (1 point)
C8H18(g) + 12.5O2(g) → ____CO2(g) + 9H2O(g) + heat
CH4(g) + ____O2(g) → ____CO2(g) + ____H2O(g) + heat
C3H8(g) + ____O2(g) → ____CO2(g) + ____H2O(g) + heat
C6H6(g) + ____O2(g) → ____CO2(g) + ____H2O(g) + heat
Solution :
C8H18(g) + 12.5O2(g) → __8__CO2(g) + 9H2O(g) + heat
When 1 part of octane reacts with 12.5 parts of oxygen, it gives 8 parts of carbon dioxide and 9 parts of water along with liberation of energy.
CH4(g) + __2__O2(g) → __1__CO2(g) + __2__H2O(g) + heat
When 1 part of methane reacts with 2 parts of oxygen, it gives 1 part of carbon dioxide and 2 parts of water along with liberation of energy.
C3H8(g) + __5__O2(g) → __3__CO2(g) + __4__H2O(g) + heat
When 1 part of propane reacts with 5 parts of oxygen, it gives 3 part of carbon dioxide and 4 parts of water along with liberation of energy.
C6H6(g) + __1/2__O2(g) → __6__CO2(g) + __3__H2O(g) + heat
When 1 part of propane reacts with 1/2 parts of oxygen, it gives 6 part of carbon dioxide and 3 parts of water along with liberation of energy.
ins1502 assignment 03
Answer:
I think you forgot to post the question or picture
PLSS HELPP ME i dont knowww
Answer:
non polar. polar ionic substance
NEED HELP ASAP!!!.....Which is not true about the ionic compound sodium chloride (NaCl)? A.)it was formed when electrons were shared B.)it is electrically neutral C.)it has properties different from the atoms from which it is formed D.)it is a white crystalline solid
Difference between brain and spinal cord
Pls help
If the specific heat capacity of copper is 387 J/kg/°C, then how much energy is needed to raise the temperature of 400 g of copper from 30°C to 55°C?
Answer:
Explanation:
mass = 400 grams * [1 kg/1000 grams] = 0.400 kg
c = 387 Joules / (oC * kg)
Δt = 55 - 30 = 25 oC
E = m*c * Δt
E = 0.4 * 387 * 25
E = 3870 Joules
It took 10.40 mL of a NaOH solution to neutralize 0.307 g of KHP. What is the molarity of the NaOH solution
Answer:
0.144 M
Explanation:
First we convert 0.307 g of KHP (potassium hydrogen phthalate, KHC₈H₄O₄) into moles, using its molar mass:
0.307 g ÷ 204.22 g/mol = 0.0015 mol KHP1 mol of KHP reacts with 1 mol of NaOH, that means that in 10.40 mL of the NaOH solution there were 0.0015 moles of NaOH.
Now we calculate the molarity of the NaOH solution:
10.40 mL / 1000 = 0.0104 LMolarity = 0.0015 mol / 0.0104 L = 0.144 MI need help with my chemistry but you can only choose one correct answer
Answer:
Explanation:
photosynthesis
the given chemical reaction is photosynthesis.
During photosynthesis carbon dioxide absorbed by plants reacts with water in presence of sunlight to give glucose and oxygen.
Which element has the smallest mass on the periodic table? *
O
H
Pb
He
Mg
Answer:
That should be Hydrogen.
So The second option Is legit!
Pure magnesium metal is often found as ribbons and can easily burn in the presence of oxygen. When 3.31 g of magnesium ribbon burns with 8.45 g of oxygen, a bright, white light and a white, powdery product are formed. Enter the balanced chemical equation for this reaction. Be sure to include all physical states.
Answer:
2Mg(s) + O2(g) ----->2MgO(s)
Explanation:
In writing a balanced chemical reaction equation, the rule of thumb is that the number of atoms of each element on the reactant side must be the same as the number of atoms of the same elements on the products side.
Hence for the reaction of magnesium and oxygen shown below;
2Mg(s) + O2(g) ----->2MgO(s)
We notice that there are two atoms each of magnesium and oxygen on both sides of the reaction equation hence the equation is balanced.
light energy travels in
Light energy travels in the form of waves.
Map
Formulate your hypothesis.
List down the materials.
• Write the methods.
Answer:
How to Formulate an Effective Research Hypothesis
State the problem that you are trying to solve. Make sure that the hypothesis clearly defines the topic and the focus of the experiment.
Try to write the hypothesis as an if-then statement. ...
Define the variables.
Explanation:
how do the hydrosphere and atmosphere interact? give an example
Answer:
Evaporation
Explanation:
Water in the ocean, rivers, lakes, etc. is part of the hydrosphere, and when that water evaporates it enters the atmosphere
HELP! ASAP! Iron (Fe) and copper (II) chloride (CuCl2) combine to form iron (III) chloride (FeCl3) and copper (Cu). If you start with 155,8 grams of
iron (Fe), how many grams of copper (Cu) will be produced?
2Fe + 3CuCl2 à 2FeCl3 + 3Cu
Answer: 30.978
Explanation:
From the equation 2 moles of Fe will result in 3 moles copper
so .325 moles Fe will result in .4875 moles Cu
Cu weights 63.546 gm per mole
.4875 moles * 63.546 gm / mole = 30.978 gm of Cu
When an acetic acid solution is titrated with sodium hydroxide, the slope of the titration curve (pH versus volume of NaOH added) increases when sodium hydroxide is first added. This change shows that ________
Answer:
When an acetic acid solution is titrated with sodium hydroxide, the slope of the titration curve (pH versus volume of NaOH added) increases when sodium hydroxide is first added. This change shows that acetic acid is being converted to sodium acetate.
Explanation:
ABOUT TITRATION - Titration is a chemical analysis method for determining the amount of a constituent in a sample by adding an exact known quantity of another substance to the measured sample with which the desired constituent reacts in a specific, known proportion. A burette, which is essentially a long, graduated measuring tube with a stopcock and a delivery tube at the bottom end, is used to gradually administer a standard solution of titrating reagent, or titrant.
It is feasible to identify a good visual color indicator for many titration processes that will signify the end point at, or very near to, the equivalence point.
Acid-base titrations, precipitation titrations, complex-formation titrations, and oxidation-reduction (redox) titrations are examples of such titrations, which are categorised according to the nature of the chemical reaction that occurs between the sample and the titrant.
Titrations of metal ions with the reagent disodium ethylenediaminetetraacetate are the most important titrations based on complex-formation processes (a salt of edetic acid, or EDTA).
Hence , the answer is that acetic acid is converted into sodium acetate.
Explain why the coefficients on the left side of the equation don’t necessarily equal the coefficients on the right side of the equation. Is this possible if mass is being conserved?
Answer:
Explanation:
Short answer: Yes.
The coefficients may not be conserved, but mass always has to be. Take this equation as an example
2 Mg3P2 ===> 6Mg + P4
There is a 2 on the left side and 6 and 1 on the right. I hope you mean that the coefficient 2 is not equal to 7.
But let's look a little closer. You have to look at the molecular structure of the left and right side.
2Mg3P2 has 6 Mgs and 4 Ps on the left side.
6Mg is on the right. They are free standing.
P4 has 1 molecule consisting of 4 Ps.
Everything balances.
This is a terrific question to be asking. You need to understand the internal balance numbers vs the molecular ones on the out side.
That sounds like a bit of gobbledygook and it takes a bit of study.
2 Mg3P2 means that Mg3P2 is written twice.
Mg3P2 ==> "3 Mg2+ + 2P3+ and there is another one written the same way.
Mg3P2 ==> "3 Mg2+ + 2P3+
1. What happens when like charges are brought closer to each other?
Which of these is an ion with a charge of 1+?
What transition energy corresponds to an absorption line at 460 nm?
A. 6.52 x 10-19 J
B. 4.32 x 10-19 J
C. 4.45 x 10-19 J
D. 2.31 x 10-19 J
Answer:
B. 4.32 x 10-19 J is correct via a p e x
Explanation:
help please hurry lots of points
What do all fossil fuels have in common?
O A. They are all liquids.
OB. They all contain crude oil.
O C. They all produce nitrogen as a combustion product.
O D. They are all nonrenewable energy sources.
Answer:
Your answer would be D, they are all non-renewable energy sources. Hope this helps!
Answer:
D. They are all nonrenewable energy sources.
a. acidic
b. basic
; neutral
d. will not be affected
Find the molarity of 10% NaOH.[MOE 2003
a. 1.5
b! 2.5
c. 4
d. 0.4
10 ml of 2.5 N NaOH is mixed with 20 ml of
N HCI. The mixture is diluted to 100 ml. WI
is the nature of mixture?
IMOF 20
1. You didn't post the question to Number 1.
2.
10% means There's 10g in 100ml of this solution.
This is the weight/volume(w/v) expression of concentration.
So
We have Mass =10g
volume =100ml
Molarity = Moles of solute/volume of solution(in LITRES)
Moles=Mass/Molar mass
Molar mass of NaOH=40g/mol
Mole=10/40
=0.25mole
Volume =100ml =0.1Litres
MOLARITY=0.25/0.1 =
=2.5M
OPTION B.
3. NOTE: THE MOLARITY AND NORMALITY OF NAOH AND HCL ARE THE SAME(This doesn't happen for all compounds tho)
So We can take 2.5N(Normality) of NaOH to be 2.5M(Molarity) NaOH
I think you forgot to write the Normality of the second one. I'll take it to be 1N. Maybe you can then Input supposed value when you're solving on your own
So
1N HCl is same as 1M HCL
We were given their respective volumes
2.5M NaOH can also be written as 2.5mole/volume(in Liters)
The volume of NaOH =10ml or 0.01L
Moles = 2.5mole/L x 0.01L
You notice that Liters on top and bottom cancels out... leaving the moles
So
Mole=0.01x2.5 = 0.025moles of NaOH
we're gonna do the same for 1N HCl in 20ml(0.02L)
So
Mole = 1 x 0.02 =0.02moles
Total Mole = 0.02 + 0.025 =0.045moles
The Final Volume is 100ml as stated in the question. It was diluted to 100ml or 0.1L
So
Final Concentration In Molarity
= Total Moles/Volume in L
=0.045/0.1
=0.45M.
A 1.0 kg bottle of sodium carbonate (Na2CO3, 106.0 g/mol) is available to clean up 5.00 liters of spilled concentrated aqueous hydrochloric acid (9.75 M). Is this enough sodium carbonate to neutralize the acid according to the following reaction?
2 HCl (aq) + Na2CO3 (s) 2NaCl (aq) + CO2 (g) + H2O (l)
(1) No, there is approximately 40% too small amount of sodium carbonate needed.
(2) Yes, there is approximately 80% more than what is needed.
(3) No, there is approximately 60% too small amount of sodium carbonate needed.
(4) Yes, there is exactly enough sodium carbonate, but no excess.
(5) No, there is approximately 20% too small amount of sodium carbonate needed.
Answer:
The correct answer is option 4, that is, there is exactly enough sodium carbonate.
Explanation:
Based on the given question, the reaction will be,
2 HCl (aq) + Na2CO3 (s) ⇒ 2 NaCl (aq) + CO2 (g) + H2O (l)
Therefore, for neutralizing 2 moles of HCl, one mole of Na2CO3 is required.
No of moles present in 1 Kg or 1000 grams of Na2CO3 will be,
Moles = Weight/Molecular mass of Na2CO3
Moles = 1000 / 106 = 9.43
Thus, 9.43 moles of Na2CO3 is present.
No of moles present in 1 liter of 9.75 M HCl is 9.75.
No. of moles present in 5 Liters of HCl (9.75 M),
= 5 × 9.75 = 48.75
Thus, for 2 moles of HCl 1 mole of Na2CO3 is required. Now for 48.75 moles of HCl, the moles required of Na2CO3 is 9.75. Therefore, for complete neutralization, the moles of Na2CO3 required is 9.75, and the present moles is 9.43.
Hence, there is exactly enough sodium carbonate.
Water moves on, above or under the surface of the Earth true or false
above because its above
2) A 0.77 mg sample of nitrogen gas reacts with chlorine gas to form 6.61 mg of a nitrogen
chloride compound. What is the empirical formula of the nitrogen chloride compound?
Answer:
NCl₃
Explanation:
From the question given above, the following data were obtained:
Mass of nitrogen (N) = 0.77 mg
Mass of chlorine (Cl) = 6.61 mg
Empirical formula =?
The empirical formula of the compound can be obtained as follow:
N = 0.77 mg
Cl = 6.61 mg
Divide by their molar mass
N = 0.77 / 14 = 0.055
Cl = 6.61 / 35.5 = 0.186
Divide by the smallest
N = 0.055 / 0.055 = 1
Cl = 0.186 /0.055 = 3
Therefore, the empirical formula of the compound is NCl₃
The area of a telescope lens is 6507 x 10^3 mm^2. What is the area in square feet, enter your answer in scientific notation. If it takes a technician 51.6 s to polish 1.68 x 10^2 mm^2 how long does it take her to polish the entire lens ?
Answer: the area of the telescope lens is \textit{0,08507 ft}
Explanation: Happy I could help!
A 0.200 M solution of a week acid, HA, is 9.4% ionized. The molar concentration of H+ is 0.0188 M. the Acid-dissociation constant, Ka, for HA is...?
We are given:
Initial concentration of HA: 0.200 Molar
The acid is 9.4% ionized
Dissociation constant (α) = (Percent Ionized) / 100 = 0.094
Molar concentration of H+ = 0.0188
Let's Chill! (making the ICE box):
Reaction: HA ⇄ H⁺ + A⁻
Initial: 0.200M - -
Equilibrium: 0.200(1-α) 0.200α 0.200α
while we're here, let's confirm the given equilibrium concentration of H⁺ ions
from the table here, we can see that the equilibrium concentration of H⁺ ions is 0.200α, we know that α = 0.094
[H⁺] = 0.200α = 0.200 * 0.094 = 0.0188 M
which means that we're on the right track
We're basically scientists at this point (finding the dissociation constant):
Acid dissociation is nothing but the equilibrium constant, but for the dissociation of Acids
From the reaction above, we can write the equation of the acid dissociation constant:
Ka = [H⁺][A⁻] / [HA]
now, let's take the values from the 'equilibrium' row of the ice box the plug those in this equation
Ka = (0.200α)(0.200α) / [0.200(1-α)]
Ka = (0.200α)²/[0.200(1-α)]
plugging the value of α
Ka = (0.200*0.094)² / [0.200(0.906)]
Ka = (0.0188)² / 0.1812
Ka = 1.95 * 10⁻³
How many atoms in total are there in 7.35 mol of magnesium oxide (MgO)
molecules?
Answer:
4.42 x 10^24
Explanation:
g (2pts) A 10x transfer buffer solution is 250mM Tris and 1.92M glycine. Buffers are always used at 1x concentration in the lab (unless specified otherwise in the protocol), so we will have to dilute the 10x buffer to 1x before use. What is the concentration of Tris and glycine in the 1x buffer
Answer:
The explanation according to the given question is summarized below.
Explanation:
Given:
Tris,
= 250 mM
Glycine,
= 1.92 M
According to the solution,
For the dilution pf 10X to 1X buffer, we get
= [tex]1 \ ml \ of \ 10X \ buffer +9 \ ml \ of \ distilled \ water[/tex]
= [tex]10[/tex]
i.e.,
⇒ [tex]10X \ to \ 1X=1:10 \ dilution[/tex]
Now,
⇒ [tex]10X (250 \ mM\ Tris \ HCl, 1.92M\ Glycine, and\ 1 \ percent (\frac{w}{v} ) SDS) ---->1X(25 \ mM \ Tris \ HCl,0.193 M\ Glycine, and \ 0.1 \ percent(\frac{w}{v} )SDS)[/tex]