Explanation:
As a number of glassware are used in lab experiments so it is necessary that they should be cleaned properly after and before the experiment.
This can be done as follows.
1). At first acetone is used to rinse the glassware. If water soluble contents present in the glassware then use deionized water after rinsing it with acetone and if ethanol soluble components are present there then rinse with ethanol followed by rinses with deionized water.
2). When glassware are dirty in such a manner that they cannot be washed immediately then soak them in water for a certain period of time. This can help in removing the dirt or chemicals easily from the glassware.
3). The laboratory glassware can be easily washed with detergents or products like lab wash, alconox etc. Once these glassware are thoroughly cleaned then rinse them 3 times with deionized water.
How does the law of conservation of mass relate to the number of atoms of each element that are present before a reaction vs. the number of atoms of each element that are present after a chemical reaction?
How many 250 mg tablets of metronidazole are needed to make 150 mL of suspension containing
100 mg/mL?
a. 25
b. 30
c. 50
d. 60
Answer:
How many 250 mg tablets of metronidazole are needed to make 150 mL of suspension containing
100 mg/mL?
a. 25
b. 30
c.50
d. 60
Explanation:
if mali po I'm so sorry
About 60 tablets of 250 mg tablets of metronidazole are needed to make 150 mL of suspension containing 100 mg/mL.
To calculate the number of tablets needed, we can use the following formula:
Number of tablets = (Desired total mass of metronidazole) / (Mass of one tablet)
The desired total mass of metronidazole in the suspension is given as 100 mg/mL × 150 mL = 15000 mg.
Since each tablet contains 250 mg of metronidazole, we can calculate the number of tablets as:
Number of tablets = 15000 mg / 250 mg = 60 tablets
Therefore, the correct answer is d. 60 tablets.
Learn more about metronidazole here:
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#SPJ 2
The decomposition of SO2Cl2 is first order in SO2Cl2 and has a rate constant of 1.42 x 10-4
s
-1 at a
certain temperature.
a. If the reaction started with 75.6 g of SO2Cl2 dissolved in 1.25 L, what would be the
concentration of SO2Cl2 after 3.00 hours?
b. A student claims that the half life of SO2Cl2 changes as the reaction progresses. Do you agree
or disagree with the students claim? Explain your answer. Note: The experiment was
preformed at a constant temperature.
Answer:
a. 13.0g/L is the concentration of SO2Cl2 after 3.00h
b. FALSE
Explanation:
The first order reaction follows the equation:
ln[SO2Cl2] = -kt + ln[SO2Cl2]₀
Where [] is the concentration after time t, k is rate constant = 1.42x10⁻⁴s⁻¹
[]₀ is initial concentration:
a. []₀ = 75.6g/1.25L = 60.48g/L
t in seconds: 3h * (3600s / 1h) = 10800s
Replacing:
ln[SO2Cl2] = -1.42x10⁻⁴s⁻¹*10800s + ln[60.48g/L]₀
ln[SO2Cl2] = 2.5687
[SO2Cl2] = 13.0g/L is the concentration of SO2Cl2 after 3.00h
b. The rate constant of a reaction remains constant if temeprature remains constant.
Suppose that you add 29.2 g of an unknown molecular compound to 0.250 kg of benzene, which has a K f of 5.12 oC/m. With the added solute, you find that there is a freezing point depression of 2.78 oC compared to pure benzene. What is the molar mass (in g/mol) of the unknown compound
Answer:
Suppose that you add 29.2 g of an unknown molecular compound to 0.250 kg of benzene, which has a K f of 5.12 oC/m. With the added solute, you find that there is a freezing point depression of 2.78 oC compared to pure benzene. What is the molar mass (in g/mol) of the unknown compound
Explanation:
The mass of nonvolatile solute added is ---- 29.2g
The mass of solvent benzene is ---- 0.250kg = 250g
The Kf value of benzene is ---- 5.12^oC/m.
Depression in the freezing point of the solution is --- 2.78^oC.
What is the molar mass of the unknown solute?
[tex]The depression in freezing point = Kf * molality of the solution\\molality of the solution = \frac{mass of solute}{molar mass of solute}*\frac{1}{mass of solvent in kg}[/tex]
Substitute the given values in this formula to get the molar mass of unknown solvent:
[tex]molality=\frac{29.2g}{M} * \frac{1}{0.250kg} \\depression in freezing point:\\2.78^oC=5.12^oC/m * \frac{29.2g}{M} * \frac{1}{0.250kg} \\\\=>M=5.12^oC/m * \frac{29.2g}{2.78^oC} * \frac{1}{0.250g} \\\\\\=>M=215.1g/mol[/tex]
Hence, the molar mass of unknown solute is --- 215g/mol.
The energy released by a nuclear fusion reaction is produced when
A.
energy is converted to mass
B.
mass is converted to energy
C.
heat is converted to temperature
D.
temperature is converted to heat
The nuclear fusion results in the liberation of large amount of energy by the conversion of mass to energy. Thus, option B is correct.
The nuclear fusion has been a type of nuclear reaction in which the reaction of the two nuclei results in the nuclei with mass smaller than the reactants. In nuclear reactions, there has been the liberation of large amount of energy.
The energy released in the nuclear fusion has been formed by the conversion of the mass. Since, the formed product has nuclei with the mass smaller than the reactants, the remaining mass of the reactants has been converted to the energy.
Thus, in nuclear fusion, the energy released has been produced from the conversion of mass to energy. Thus, option B is correct.
For more information about the nuclear fusion, refer to the link:
https://brainly.com/question/16021285
The information code that an organism inherits can best be referred to as its -
O A genotype
B. territory
C. species
D. kingdom
Answer:
it will be no.A genotype
3. Which of the following can be physically separated?
Answer:
mixture
Explanation:
an example of one is a salad you can separate the ingredients
Determine the electron geometry, molecular geometry, and idealized bond angles for each of the following molecules. CF4CF4 NF3NF3 OF2OF2 H2SH2S In which cases do you expect deviations from the idealized bond angle
Answer:
CF4
Molecular geometry- tetrahedral
Electron geometry- tetrahedral
NF3
-molecular geometry - trigonal pyramidal
Electron geometry - tetrahedral
OF2
Molecular geometry - bent
Molecular geometry - tetrahedral
H2S
Molecular geometry- bent
Electron geometry - tetrahedral
Explanation:
According to Valence Shell Electron Pair Repulsion Theory, the shape of a molecule depends on the number of electron pairs on the valence shell of the central atom in the molecule.
For all the compounds listed, the central atom has four points of electron density. This correspond to a tetrahedra electron pair geometry. The presence of lone pairs on the central atom of OF2,NF3 and H2S accounts for the departure of the observed molecular geometry from the geometry and idealized bond angle predicted on the basis of the VSEPR theory.
FULL FORM OF NASA??
lol
Answer:
NASA stands for National Aeronautics and Space Administration
Answer:
National Aeronautics and Space Administration
hope this will help you more
material or substance a wave transfers energy through what
Answer:
waves, energy is transferred through vibrations of electric and magnetic fields.
Explanation:
In sound waves, energy is transferred through vibration of air particles or particles of a solid through which the sound travels. In water waves, energy is transferred through the vibration of the water particles
In the following structure, carbons (I),(2),(3) and (4) are classified respectively as
Answer:
Carbon (i) : quaternary carbon
Carbon (ii) : secondary carbon
Carbon (iii) : tertiary carbon
Carbon (iv) : secondary carbon
Explanation:
Carbons can be classified into 4 categories:
(1) Primary carbon [tex](1^o)[/tex]: These are the atoms where the carbon atom is attached to one other carbon atom.
(2) Secondary carbon [tex](2^o)[/tex]: These are the atoms where the carbon atom is attached to two other carbon atoms.
(3) Tertiary carbon [tex](3^o)[/tex]: These are the atoms where the carbon atom is attached to three other carbon atoms.
(4) Quaternary carbon [tex](4^o)[/tex]: These are the atoms where the carbon atom is attached to four other carbon atoms.
In the given structure:
Carbon (i) is attached to 4 further carbon atoms and hence, it is a quaternary carbon.
Carbon (ii) is attached to 2 further carbon atoms and hence, it is a secondary carbon.
Carbon (iii) is attached to 3 further carbon atoms and hence, it is a tertiary carbon.
Carbon (iv) is attached to 2 further carbon atoms and hence, it is a secondary carbon.
A buffer solution contains 0.475 M nitrous acid and 0.302 M sodium nitrite . If 0.0224 moles of potassium hydroxide are added to 150 mL of this buffer, what is the pH of the resulting solution
Answer: The pH of the resulting solution will be 3.001
Explanation:
Molarity is calculated by using the equation:
[tex]\text{Molarity}=\frac{\text{Moles}}{\text{Volume}}[/tex] ......(1)
We are given:
Moles of NaOH = 0.0224 moles
Molarity of nitrous acid = 0.475 M
Molarity of sodium nitrite = 0.302 M
Volume of solution = 150 mL = 0.150 L (Conversion factor: 1 L = 1000 mL)
Putting values in equation 1, we get:
[tex]\text{Moles of nitrous acid}=(0.475mol/L\times 0.150L)=0.07125mol[/tex]
[tex]\text{Moles of sodium nitrite}=(0.302mol/L\times 0.150L)=0.0453mol[/tex]
The chemical equation for the reaction of nitrous acid and NaOH follows:
[tex]HNO_2+NaOH\rightleftharpoons NaNO_2+H_2O[/tex]
I: 0.07125 0.0224 0.0453
C: -0.0224 -0.0224 +0.0224
E: 0.04885 - 0.0677
The power of the acid dissociation constant is the negative logarithm of the acid dissociation constant. The equation used is:
[tex]pK_a=-\log K_a[/tex] ......(2)
We know:
[tex]K_a[/tex] for nitrous acid = [tex]7.2\times 10^{-4}[/tex]
Using equation 2:
[tex]pK_a=-\log (7.2\times 10^{-4})=3.143[/tex]
To calculate the pH of the acidic buffer, the equation for Henderson-Hasselbalch is used:
[tex]pH=pK_a+ \log \frac{\text{[conjugate base]}}{\text{[acid]}}[/tex] .......(3)
Given values:
[tex][NaNO_2]=\frac{0.0677}{0.150}[/tex]
[tex][HNO_2]=\frac{0.04885}{0.150}[/tex]
[tex]pK_a=3.143[/tex]
Putting values in equation 3. we get:
[tex]pH=3.143-\log \frac{(0.0677/0.150)}{(0.04885/0.150)}\\\\pH=3.143-0.142\\\\pH=3.001[/tex]
Hence, the pH of the resulting solution will be 3.001
On another planet, the isotopes of titanium have the given natural abundances.
Isotope Abundance Mass (u)
46Ti 77.100% 45.95263
48Ti 17.100% 47.94795
50Ti 5.800% 49.94479
What is the average atomic mass of titanium on that planet?
Answer:
46.525 u
Explanation:
From the question given above, the following data were obtained:
Isotope A (⁴⁶Ti)
Abundance (A%) = 77.100%
Mass of A = 45.95263 u
Isotope B (⁴⁸Ti):
Abundance (B%) = 17.100%
Mass of B = 47.94795 u
Isotope C (⁵⁰Ti):
Abundance (C%) = 5.800%
Mass of C = 49.94479 u
Average atomic mass =?
The average atomic mass of titanium can be obtained as follow:
Average = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100]
= [(45.95263 × 77.1)/100] + [(47.94795 × 17.1)/100] + [(49.94479 × 5.8)/100]
= 35.429 + 8.199 + 2.897
= 46.525 u
Therefore, the average atomic mass of titanium is 46.525 u
Which of the following has the highest pH?
A. 0.01 M HCI
B. 0.1 M HCI
C. 1 M HCI
D. 0.001 M HCI
Answer:
D
Explanation:
pH=-log(x)
x=0.001M,pH=3
x=0.01M,pH=2
x=0.1M,pH=1
x=1M,pH=0
Highest pH is for option D
Answer:
D.
Explanation:
The highest pH is D because
0.01 M HCL => 2
0.1 M HCL => 1
1 M HCL => 0
0.001 M HCL => 3
so the answer is D.
Discuss the any two applications of Beer’s law with suitable justification.
Answer: It's used in chemistry to measure the concentration of chemical solutions.
Explanation:
Beer's Law is used in chemistry to measure the concentration of chemical solutions, to analyze oxidation, and to measure polymer degradation.
The law also describes the attenuation of radiation through the Earth's atmosphere
Calcula la concentración de H+ de una sustancia que tiene pH 8.8
Answer:
[tex]pH = - log[H {}^{ + } ] \\ 8.8 = - log[H {}^{ + } ] \\ \: [H {}^{ + } ] = {10}^{ - 8.8} \\ [H {}^{ + } ] = 1.585 \times {10}^{ - 9} \: mol {dm}^{ - 3} [/tex]
A 250ml sample of sir at 373.15k is warmed at 473.15 at constant pressure. What is the volume of the air sample at the new temperature
Answer:
317 mL.
Explanation:
From the question given above, the following data were obtained:
Initial volume (V₁) = 250 mL
Initial temperature (T₁) = 373.15 K
Final temperature (T₂) = 473.15 K
Pressure = Constant
Final volume (V₂) =?
The final volume of the air sample can be obtained by using the Charles' law equation as illustrated below:
V₁/T₁ = V₂/T₂
250 / 373.15 = V₂ / 473.15
Cross multiply
373.15 × V₂ = 250 × 473.15
373.15 × V₂ = 118287.5
Divide both side by 373.15
V₂ = 118287.5 / 373.15
V₂ = 317 mL
Therefore, the final volume of the air sample is 317 mL
sino may kuyang palaging nambibira
What is a combustion reaction
Answer:
Combustion, a chemical reaction between substances, usually including oxygen and usually accompanied by the generation of heat and light in the form of flame.
Explanation:
Hope this helps!! :))
A 575.4575.4 mL sample of carbon dioxide was heated to 377377 K. If the volume of the carbon dioxide sample at 377377 K is 824.7824.7 mL, what was its temperature at 575.4575.4 mL
Answer:
263 K
Explanation:
Assuming ideal behaviour and constant pressure, we can solve this problem by using Charles' law, which states that at constant pressure:
T₁V₂=T₂V₁In this case:
T₁ = ?V₂ = 824.7 mLT₂ = 377 KV₁ = 575.45 mLWe input the data:
T₁ * 824.7 mL = 377 K * 575.45 mLAnd solve for T₁:
T₁ = 263 K50.00 mL of unknown calcium hydroxide solution is titrated with 0.250 M standard nitric acid solution. If 43.43 mL of the standard acid solution is required to reach a phenolphthalein endpoint, what is the molarity of the unknown calcium hydroxide solution
Answer: Molarity of the unknown calcium hydroxide solution is 0.217 M.
Explanation:
Given: [tex]V_{1}[/tex] = 50.00 mL, [tex]M_{1}[/tex] = ?
[tex]V_{2}[/tex] = 43.43 mL, [tex]M_{2}[/tex] = 0.250 M
Formula used is as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}[/tex]
Substitute the values into above formula as follows.
[tex]M_{1}V_{1} = M_{2}V_{2}\\M_{1} \times 50.00 mL = 0.250 M \times 43.43 mL\\M_{1} = \frac{0.250 M \times 43.43 mL}{50.00 mL}\\= 0.217 M[/tex]
Thus, we can conclude that molarity of the unknown calcium hydroxide solution is 0.217 M.
How many line pairs of electrons does a square planar molecule have?
2
0
6
4
Answer:
the answer is 4 hope this helps
Use collision theory to describe the relationship between temperature and volume of a gas.
Answer:
Charles's law 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.
C8H18+O2=CO2+H2O. Balance this equation and identify the number H2O molecules formed when 6 molecules of C8H18 react with 75 molecules of oxygen
Answer: 54 molecules of water will be formed in the reaction.
Explanation:
A balanced chemical equation is one where all the individual atoms are equal on both sides of the reaction. It follows the law of conservation of mass.
For the given unbalanced chemical equation, the balanced equation follows:
[tex]2C_8H_{18}+25O_2\rightarrow 16CO_2+18H_2O[/tex]
We are given:
Molecules of [tex]C_8H_{18}[/tex] = 6
Molecules of [tex]O_2[/tex] = 75
By the stoichiometry of the reaction:
If 2 molecules of [tex]C_8H_{18}[/tex] produces 18 molecules of water
So, 6 molecules of [tex]C_8H_{18}[/tex] will produce = [tex]\frac{18}{2}\times 6=54[/tex] molecules of water
Hence, 54 molecules of water will be formed in the reaction.
An atom has the electron configuration of 1s22s22p5 how many electrons are in that atom
Answer:
There are [tex]9[/tex] electrons in this atom.
Explanation:
Electron configuration of this atom: [tex]1s^2\, 2s^2\, 2p^5[/tex].
The electron orbitals of an atom are denoted as [tex]1s[/tex], [tex]2s[/tex], [tex]2p[/tex], [tex]3s[/tex], [tex]3p[/tex], etc. At any given time, an electron in this atom is located in exactly one orbital.
The electron configuration of an atom gives the number of electrons in each orbitals of this atom.
For example, in this atom, the superscript "[tex]2[/tex]" on the right of "[tex]1s[/tex]" means that there are two electrons in the [tex]1s\![/tex] orbital of this atom. Hence, [tex]1s^2\, 2s^2\, 2p^5[/tex] would translate to:
The [tex]1s[/tex] orbital of this atom contains [tex]2[/tex] electrons.The [tex]2s[/tex] orbital of this atom contains [tex]2[/tex] electrons.The [tex]2p[/tex] orbitals of this atom contain [tex]5[/tex] electrons.Hence, there would be [tex]2 + 2 + 5 = 9[/tex] electrons in total in this atom.
You have selected your two primers and added all of the PCR components to a test tube. Use the answer choices [A-C] to explain what will happen as the polymerase chain reaction proceeds. Answers may be used more than once or not at all.
Hi. You did not provide any response options. However, a PCR reaction proceeds as follows.
After the primers are added to the test tube containing the PCR components. This tube is placed in a device called a thermocycler. At that moment, the stage called denaturation will begin, where the thermocycler increases the temperature to the point of breaking the hydrogen bonds that hold the two strands of DNA together. The thermal cycler increases the temperature up to 96°C.
After that, the second step of the reaction begins. At that moment, the thermal cycler lowers the temperature to 55º - 65ºC, which is the ideal temperature for the primers to be able to attach themselves to the DNA strands, preparing them for the presence of the polymerase.
After that, the thermocycler raises the temperature to 72ºC, which is the ideal temperature for the DNA polymerase to work. At this stage, the DNA polymerase will use the DNA strand and the primer to build a new DNA strand, which will be annealed to the DNA strand used as a template.
These three steps will be repeated about 35 times, generating many copies of DNA.
When an atom becomes charged what is transferred?
Answer:it becomes positively charged
Explanation:Some atoms can attract additional electrons so they become negatively charged.
An unknown element, X, has an atomic mass of 107.868 amu. The X-109 isotope (108.905 amu) is 48.16%. What is the amu of the other isotope (report final answer to the correct number of significant figures)
Answer:
106.905 amu is the mass of the other isotope
Explanation:
The atomic mass of an element is the sum of the masses of the isotopes multiplied by its abundance. The atomic mass of an element X with 2 isotopes is:
X = X-109*i + X-107*i
Where X is the atomic mass = 107.868 amu
X-109 = 108.905amu, i = 48.16% = 0.4816
X-107 = ?, i = 1-0.4816 = 0.5184
Replacing:
107.868amu = 108.905amu*0.4816 + X-107*0.5184
55.4194 = X-107*0.5184
106.905 = X-107
106.905 amu is the mass of the other isotopeTHE DIAMETER OF A TAMBOURINE IS 10 INCHES.FIND THE AREA OF ITS SURFACE.USE π=3.14.
1.What is ask in the problem?
2.What are the given facts?
3.What operation to be used?
4.What is the number sentence
5.What is the answer?
Answer:
22/7 × [tex]10^{2}[/tex]
Explanation:
The area of a circle can be found out using π[tex]r^{2}[/tex]. Since r is the radius so if they multiply, they will give you an area of a square then multiply by 22/7 since it is a circle.
The surface area of the Tambourine at the given diameter of 10 inches is determined as 78.54 square inches.
Area of the TambourineA Tambourine has circular shape, and the area of the Tambourine can be determined by applying formula for area of a circle as shown below;
A = πr²
where;
r is the radius of the circleRadius of the Tambouriner = ¹/₂D
r = ¹/₂ x 10 in
r = 5 in
A = π(5)²
A = 25π in²
A = 78.54 in²
Thus, the surface area of the Tambourine at the given diameter of 10 inches is determined as 78.54 square inches.
Learn more about surface area here: https://brainly.com/question/76387
Write the molecular formula for the compound that exhibits a molecular ion at M+ = 112.0499. Assume that C, H, N, and O might be present, and use the exact masses below: Exact mass of carbon = 12.000 Exact mass of hydrogen = 1.0078 Exact mass of nitrogen = 14.003 Exact mass of oxygen = 15.995 (The order of atoms should be carbon, then hydrogen, then the others in alphabetical order. If there is more than one answer, just give one. ) Molecular formula:
Answer:
C₅H₈N₂O
Explanation:
The molecular formula denotes the various forms of atoms contained in a molecule at a particular fixed proportion.
The molecular ion M⁺ = 112.0499
and the exact mass values are given as follows:
C = 12.000
H = 1.0078
N = 14.003
O = 15.995
By assumption:
C = 12.000 × 5 = 60.0000
H = 1.0078 × 8 = 1.0078
N = 14.003 × 2 = 28.0060
O = 15.995 × 1 = 15.9950
= 112.0634
This is approximtely equal to 112.0499.
As such the Molecular formula for the compound = C₅H₈N₂O
