Answer:
I hope this helps!
Explanation:
The biggest threat caused by GM foods is that they can have harmful effects on the human body. It is believed that consumption of these genetically engineered foods can cause the development of diseases which are immune to antibiotics. ... As the health effects are unknown, many people prefer to stay away from these foods.
5) When heated in a flame, the element Indium emits electromagnetic radiation with a distinctive indigo blue
color (the name indium is derived from the word indigo). The emitted photons that give rise to this
color
have energies of 4.405 x 10^-19J. Calculate the wavelength of this radiation in nanometers.
Answer:
[tex]\lambda=451nm[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to solve this problem by using the following equation, defined in terms of energy, Planck's constant, wavelength and speed of light:
[tex]E=\frac{hC}{\lambda }[/tex]
Thus, we solve for the wavelength as shown below:
[tex]\lambda=\frac{hC}{ E}[/tex]
And finally plug in the energy, Planck's constant and speed of light to obtain:
[tex]\lambda=\frac{6.6261 x 10^{-34} m^2 kg / s*3x10^8m/s}{4.405x10^{-19}m^2kg/s^2}\\\\\lambda=4.513x10^{-7}m*\frac{1nm}{10^{-9}m} \\\\\lambda=451nm[/tex]
Regards!
What will be the equilibrium temperature when a 245 g block of lead at 300oC is placed in 150-g aluminum container containing 820 g of water at 12.0oC?
Answer:
The correct approach is "12.25°C".
Explanation:
Given:
Mass of lead,
mc = 245 g
Initial temperature,
tc = 300°C
Mass of Aluminum,
ma = 150 g
Initial temperature,
ta = 12.0°C
Mass of water,
mw = 820 g
Initial temperature,
tw = 12.0°C
Now,
The heat received in equivalent to heat given by copper.
The quantity of heat = [tex]m\times s\times t \ J[/tex]
then,
⇒ [tex]245\times .013\times (300-T) = 150\times .9\times (T-12.0) + 820\times 4.2\times (T-12.0)[/tex]
⇒ [tex]3.185(300-T) = 135(T-12.0) + 3444(T-12.0)[/tex]
⇒ [tex]955.5-3.185T=135T-1620+3444T-41328[/tex]
⇒ [tex]43903.5 = 3582.185 T[/tex]
⇒ [tex]T = 12.25^{\circ} C[/tex]
A student pours a few drops of vinegar onto limestone and it starts bubbling. What kind of reaction is this? How does it relate to chemical weathering, monuments and statues?
Answer:
The correct answer is - acid-base reaction or chemical weathering.
Explanation:
Vinegar is an acid that dissolves a material that is commonly found and known as calcium carbonate present in the limestone. When these two, vinegar mix with calcium carbonate of the limestone, the atoms in the acetic acid and the calcium carbonate come apart and rearrange in different ways to make new chemicals.
This rearrangement results in the release of carbon dioxide as a stream of bubbles. It is a form of weathering called chemical weathering and many monuments are based on rocks that have limestones in their composition and acid rain work similar to vinegar.
Hydrogen gas and fluorine gas will react to form hydrogen fluoride gas. What is the standard free energy change for this reaction
Answer:
[tex]\Delta G=-541.4kJ/mol[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out firstly necessary to write out the described chemical reaction as shown below:
[tex]H_2+F_2\rightarrow 2HF[/tex]
Now, we set up the expression for the calculation of the standard free energy change, considering the free energy of formation of each species, specially those of H2 and F2 which are both 0 because they are pure elements:
[tex]\Delta G=2\Delta G_f^{HF}-(\Delta G_f^{H_2}+\Delta G_f^{F_2})\\\\\Delta G=2*-270.70kJ/mol-(0kJ/mol+0kJ/mol)\\\\\Delta G=-541.4kJ/mol[/tex]
Regards!
Physical and psychological dependence, high-risk behaviour, and chronic high blood
pressure can result from excessive use of
Answer:
Physical and psychological dependence is high, and withdrawal symptoms include watery eyes, runny nose, loss of appetite, irritability, tremors, panic, abdominal cramps and diarrhea, nausea, chills, and sweating. Use of contaminated syringes/needles to inject drugs may result in serious blood borne infections such as HIV-AIDS and hepatitis.
Based on the electron configuration of the two atoms, predict the ratio of metal cationic (+) atom to nonmetal anionic (-) atom in the compound.
Lithium 1s^22s^1
Chlorine 1s^22s^22p^6 3s^23p^5
Answer:
Option A. 1:1
Explanation:
From the question given above, the following data were obtained:
Li => 1s² 2s¹
Cl => 1s² 2s²2p⁶ 3s²2p⁵
Lithium (Li) will form compound with Cl by losing 1 electron as shown below:
Li —> Li⁺ + e¯ ..... (1)
Cl on the other hand will accept 1 electron from Li to form the chloride ion, Cl¯ as shown below:
Cl + e¯ —> Cl¯ ...... (2)
Combining equation 1 and 2, we have:
Li + Cl + e¯ —> Li⁺ + Cl¯ +
Cancel e¯ from both side
Li + Cl —> Li⁺Cl¯
Thus, the ratio of metallic cation (+) to non-metallic anion (-) in the compound is 1:1
1.0 g of a compound A is prepared in 100 mL of water, and then extracted with 50 mL of ether. After the extraction, 0.25 g of the compound was recovered from the ether layer. What is the partitioning coefficient([A]ether/[A]water) for this compound in the system used?a. 4.0b. 3.0c. 1.5d. 0.75e. 0.25f. 0.67
Answer:
uh 2
Explanation:
Its 2 cause uh 2 sounds about right
To solve this we must know the concept behind partition coefficient. The partitioning coefficient for this compound in the system used is 0.67. Therefore, the correct option is option F.
What is partition coefficient?The ratio of a solute's concentrations in two solids, immiscible liquids, or barely miscible liquids when they are in equilibrium throughout the interface connecting them is called partition coefficient.
In fundamental chemistry, partitioning is utilized to separate components in procedures like chromatography. Partitioning is a crucial factor in the distribution of chemicals and medications between the blood and bodily tissues in the field of pharmacology.
Mathematically,
partition coefficient= concentration of the solute in stationary phase/concentration of the solute in mobile phase
partition coefficient={(0.25 /M)÷50}÷{(1.0/M)÷100 }
=0.005÷0.01
=0.67
Therefore, the correct option is option F.
To learn more about partition coefficient, here:
https://brainly.com/question/29845640
#SPJ5
Consider the reaction of 2-chloro-2-methylpentane with sodium iodide.
Assuming no other changes, how would it affect the rate if one simultaneously doubled the concentration of 2-chloro-2-methylpentane and sodium iodide?
A) No effect.
B) It would double the rate.
C) It would triple the rate.
D) It would quadruple the rate.
E) It would increase the rate five times.
Answer:
Explanation:
The reaction between 2 chloro- 2 methyl pentane and sodium iodide takes place through SN2 mechanism . iodide ion is the nucleophile which attacks the substrate . The rate of such reaction depends upon concentration of both the nucleophile and the substrate .
Hence rate of reaction will be increased by 2 x 2 = 4 times.
option D ) is correct.
Explanation:
The given reaction represents the reaction between a tertiary alkyl halide that is 2-chloro-2-methylpentane and a nucleophile that is NaI.
This reaction favors SN1 mechanism which has order one.
So, the given reaction follows first-order kinetics.
For a first-order reaction, the rate law is:
rate =k [A]
That means the rate of the reaction is dependent on the concentration of reactants.
So, when the concentration of the reactant is doubled then, the rate of the reaction is also doubled.
Among the given options the correct answer is option B) It would double the rate.
2. 27.8 mL of an unknown were added to a 50.0-mL flask that weighs 464.7 g. The total mass of the flask and the liquid is 552.4 g. Calculate the density of the liquid in Lbs/ in3.
Answer:
[tex]d=4.24x10^{-4}\frac{lb}{in^3}[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out firstly necessary for us to set the equation for the calculation of density and mass divided by volume:
[tex]d=\frac{m}{V}[/tex]
Thus, we can find the mass of the unknown by subtracting the total mass of the liquid to the mass of the flask and the liquid:
[tex]m=552.4g-464.7g=87.7g[/tex]
So that we are now able to calculate the density in g/mL first:
[tex]d=\frac{87.7g}{27.8mL}=3.15g/mL[/tex]
Now, we proceed to the conversion to lb/in³ by using the following setup:
[tex]d=3.15\frac{g}{mL}*\frac{1lb}{453.6g}*\frac{1in^3}{16.3871mL}\\\\d=4.24x10^{-4}\frac{lb}{in^3}[/tex]
Regards!
Which does not result in deviations from linearity in a Beer's law plot of absorbance versus concentration?a. light losses at the cell interface b. all are sources of nonlinearity c. stray radiation d. equilibrium between different forms of the analyte e. a wide bandwidth relative to the width of the absorption band
Answer:
a
Explanation:
Beer-Lambert Law shows the relationship between the factors affecting the absorbance of a sample in relation to the concentration. These factors are:
the concentration c, path length (l), and the molar absorptivity (ε).
As a result, more radiation is assimilated as the concentration rises, and the absorbance rises as well. However, the longer the path length, the increase in the number of molecules and the higher the absorbance.
Thus, the straight-line equation for Beer-Lambert's law is:
A = εcl
From the above explanation, the option that doesn't relate to the deviations from linearity of Beer's law plot is in Option (a).
g A high altitude balloon is filled with 1.41 x 104 L of hydrogen gas (H2) at a temperature of 21oC and a pressure of 745 torr. What is the volume of the balloon at a height of 20 km, where the temperature is -48oC and the pressure is 63.1 torr
Answer:
1.27 × 10⁵ L
Explanation:
Step 1: Given data
Initial pressure (P₁): 745 TorrInitial volume (V₁): 1.41 × 10⁴ LInital temperature (T₁): 21 °CFinal pressure (P₂): 63.1 TorrFinal volume (V₂): ?Final temperature (T₂): -48 °CStep 2: Convert the temperatures to the Kelvin scale
We will use the following expression.
K = °C + 273.15
K = 21 °C + 273.15 = 294 K
K = -48 °C + 273.15 = 225 K
Step 3: Calculate the final volume of the balloon
We will use the combined gas law.
P₁ × V₁ / T₁ = P₂ × V₂ / T₂
V₂ = P₁ × V₁ × T₂/ T₁ × P₂
V₂ = 745 Torr × 1.41 × 10⁴ L × 225 K/ 294 K × 63.1 Torr
V₂ = 1.27 × 10⁵ L
Write a complete, balanced equation for the following reactions:
e) The heating of sodium carbonate (teachers note: produces sodium oxide and carbon dioxide).
f) chromium (III) hydroxide plus sulfuric acid (teachers note: You figure out products).
g) aluminum metal plus chlorine gas (teachers note: produces aluminum chloride).
Please explain as well, thanks!
Answer:
Solution given:
e) The heating of sodium carbonate to produces sodium oxide and carbon dioxide
Solution given:
Balanced chemical equation:
[tex]\boxed{\bold{\green{Na_{2}CO_{2} +heat \rightarrow Na_{2}O +CO_{2}}}}[/tex]
when sodium carbonate is heated it decomposed and form sodium oxide and carbon dioxide
f) chromium (III) hydroxide plus sulfuric acid
Balanced chemical equation:
[tex]\boxed{\bold{\green{2Cr(OH)_{3}+ 3H_{2}SO_{4} → Cr_{2}(SO_{4})_{3} + 6H_{2}O}}}[/tex]
When chromium (III) hydroxide react with sulfuric acid double displacement takes place and forms produce chromium(III) sulfate and water.
g) aluminum metal plus chlorine gas
[tex]\boxed{\bold{\green{2Al(s) + 3Cl_2(g) \rightarrow 2AlCl_2 }}}[/tex]
When aluminum metal is added to chlorine gas Combination reaction takes place and forms aluminum chloride.
e) The heating of sodium carbonate to produces sodium oxide and carbon dioxide
Solution given:
Balanced chemical equation:
[tex]\boxed{\bold{\green{Na_{2}CO_{2} +heat \rightarrow Na_{2}O +CO_{2}}}}[/tex]
when sodium carbonate is heated it decomposed and form sodium oxide and carbon dioxide
f) chromium (III) hydroxide plus sulfuric acid
Balanced chemical equation:
[tex]\boxed{\bold{\green{2Cr(OH)_{3}+ 3H_{2}SO_{4} → Cr_{2}(SO_{4})_{3} + 6H_{2}O}}}[/tex]
When chromium (III) hydroxide react with sulfuric acid double displacement takes place and forms produce chromium(III) sulfate and water.
g) aluminum metal plus chlorine gas
[tex]\boxed{\bold{\green{2Al(s) + 3Cl_2(g) \rightarrow 2AlCl_2 }}}[/tex]
When aluminum metal is added to chlorine gas Combination reaction takes place and forms aluminum chloride.
How did the work of Dmitri Mendeleev differ from that of John Newlands in the development of the periodic table?
Answer: Mendeleev predicted elements that would later be discovered.
what are the products in a chemical equation located?
Answer:
they are the end results so they are after the yields symbol
Explanation:
An experimental drug, D, is known to decompose in the blood stream. Tripling the concentration of the drug increases the decomposition rate by a factor of nine. Write the rate law for decomposition of D.
Answer:
R=k[D]^2
Explanation:
Given that it is a decomposition reaction;
D--->product
Hence;
The rate law is;
R= k[D]^x ----(1)
When we triple the concentration of D we have;
[D]' = [3D]^x
Therefore;
R'= 3R
R'= k[D]'----(2)
Hence dividing (1) by (2);
R/R' = k[D]^x/k[D]'
R/9R = k[D]^x/k[3D]^x
1/9 = 1/3^x (take inverse of both sides)
9 = 3^x
3^2 = 3^x
x= 2
Hence the rate law;
R=k[D]^2
Identify effective techniques for accurate pipet use. Select all that apply. Select one or more: Measure liquid by aligning the meniscus with the volume line. Leave any air bubbles in a pipet that occur after drawing up liquid. Do not let liquid enter the pipet bulb or pump. Use the pipet bulb to force the last drop out of the tip.
Answer:
Measure liquid by aligning the meniscus with the volume line.
Explanation:
A pipette is an instrument specially made for measuring a small volume of liquid.
The pipette comes in various sizes to be used in measuring various volumes of liquid. Generally, the pipette has a volume line which helps us to measure a liquid.
A liquid is measured by aligning the meniscus with the volume line.
Which type of element is almost always found as a single atom in nature?
O A. Alkaline earth metal
O B. Halogen
c. Noble gas
D. Oxygen family element
Noble gas elements are almost always found as a single atom in nature.
What is inert gas?An inert gas is a gas that does not undergo chemical reactions under a set of given conditions. The noble gases often do not react with many substances and were historically referred to as inert gases.
All noble gases have the maximum number of electrons in their outer shell; i.e. 2 electrons for helium and 8 for the other five.
Noble gases are monoatomic, which means they exist as single atoms. This is because of their electronic stability.
Thus, noble gas elements are almost always found as a single atom in nature. Hence, option C is correct.
Learn more about the inert gas here:
https://brainly.ph/question/4502738
#SPJ1
Fill in the left side of this equilibrium constant equation for the reaction of acetic acid HCH3CO2 with water.
______ = Ka
Answer:
The left side equation is:
[tex]Ka = \frac{[CH_{3}COO^{-}] [H_{3}O^{+}]}{[HCH_{3}COO] [H_{2}O]}[/tex]
Explanation:
For the reaction of acetic acid HCH3CO2 with the water, The equilibrium constant equation is
[tex]HCH_{3}COO + H_{2}O \rightleftharpoons CH_{3}COO^{-} + H_{3}O[/tex]
The left side of this equilibrium constant equation will be written as shown below:
[tex]Ka = \frac{[CH_{3}COO^{-}] [H_{3}O^{+}]}{[HCH_{3}COO] [H_{2}O]}[/tex]
Suppose that a certain atom possesses only four distinct energy levels. Assuming that all transitions between levels are possible, how many spectral lines will this atom exhibit
Answer:
Following are the response to the given question:
Explanation:
The number of shells
n = 4
Calculating the spectral line:
[tex]= \frac{n(n-1)}{2}\\\\ = \frac{4(4-1)}{2} \\\\= \frac{4\times 3}{2}\\\\ = \frac{12}{2}\\\\ = 6[/tex]
How many atom in protons
Answer:
Its atomic number is 14 and its atomic mass is 28. The most common isotope of uranium has 92 protons and 146 neutrons. Its atomic number is 92 and its atomic mass is 238 (92 + 146).
The product of the following reaction is
``````````````````````````````````
X = atomic number - number of core electrons
Which of the following explains the identity of X and its trends down a group?
A. X is the effective nuclear charge, and it remains constant down a group.
B. X is the screening constant, and it remains constant down a group.
C. X is the effective nuclear charge, and it increases down a group.
D. X is the screening constant, and it increases down a group.
Based on the expression given in the question, X is the effective nuclear charge, and it increases down a group.
What is an effective nuclear charge?Effective nuclear charge is the net nuclear charge that an electron in an atom experiences, after subtracting the nuclear charge shielded by other electrons.
The effective nuclear charge is denoted by Zeff and can be calculated by subtracting the number of shielding electrons from the atomic number.
Therefore, based on the expression given in the question, X is the effective nuclear charge, and it increases down a group.
Learn more about effective nuclear charge at: https://brainly.com/question/13664060
#SPJ1
You have 10 pounds of egg whites. You need 6oz to make one serving of cosomme. How many servings can you make?
Answer:
I think you can make 26, hope this helped.
Explanation:
You will observe a weak acid-strong base titration in this experiment. Select all statements that are true about weak acid-strong base titrations.
A. Weak acid-strong base titrations always start at a higher pH than strong acid-strong base titrations, no matter the initial concentration.
B. The pH is less than 7 at the equivalence point.
C. The pH is greater than 7 at the equivalence point.
D. Half way to the equivalence point, a buffer region is observed.
Answer:
The pH is greater than 7 at the equivalence point.
Explanation:
Equivalence point is the point where the acid reacts with the base as stipulated in the equation of the reaction.
When a weak acid and a strong base are titrated, the pH of the solution at equivalence point is actually found to be around about pH ~ 9.
Hence, for a weak acid and strong base titration, The pH is greater than 7 at the equivalence point.
A titration between a weak acid and a strong base yields a solution whose pH is greater than 7 at the equivalence point.
What are weak acids?Weak acids are acids which only ionize partially in aqueous solutions.
When weak acids are dissolved in water, they produce only few hydrogen ions.
A strong base on the other hand ionizes completely to produce hydroxide ions in aqueous solutions.
The titration of a weak acid and a strong base gives a solution whose pH is greater than 7 at equivalence point.
Learn more about equivalence point at: https://brainly.com/question/18933025
2. For each of the ionic compounds in the table below, name the compound and explain the rule that you
used in formulating your name for the compound.
Name:
Rule for naming compound:
-PbF4
-NH4NO3
-Li2S
Answer:
2
Explanation:
Lead(|V) fluoride
Ammonium Nitrate
Lithium sulfide
For the rules, I don't know what you were taught. I just do it intuitively since I have done so much chemistry.
The first one the roman numerals represents the charge of the lead which much match the 4- charge from the 4 fluorides.
The second one is just two polyatomic ions which you just have to remember.
The last one is the typical ionic compound naming technique i guess.
which of the following kb values represents the weakest base?
Answer:
the weakest base will have a higher Kb value since it will be closer to an acid than a base
7 kb values represents the weakest base.
What is kb value?Kb is the base dissociation constant which is a measure of how completely a base dissociates into its component ions in water. pKb is define as the negative base-10 logarithm of the base dissociation constant (Kb) of a solution.
Ka is define as the acid dissociation constant while pKa is the -log of this constant. Kb is define as the base dissociation constant, while pKb is the -log of the constant.
The acid and base dissociation constants are usually expressed in terms of moles per liter (mol/L).
Thus, 7 kb values represents the weakest base.
Learn more about Kb value, here:
https://brainly.com/question/29427601
#SPJ2
Oleic acid and elaidic acid are isomeric alkenes.
a. True
b. False
Answer:
False
Explanation:
Because Elaidic acid is an isomer of oleic acid. I really hope this helps you.
why beta carbon hydrogen is easily replaceable but not alpha carbon hydrogen
Answer:
Four common types of reactions involving carbonyl reactions: 1) nucleophilic addition; 2) nucleophilic acyl substitution; 3) alpha substitution; 4) carbonyl condensations. The first two were previously discussed and the second two involve the properties of the carbon directly adjacent to the carbonyls, α carbons.
Alpha-substitution reactions results in the replacement of an H attached to the alpha carbon with an electrophile.
The nucleophile in these reactions are new and called enols and enolates.
Explanation:
The carbon in the carbonyl is the reference point and the alpha carbon is adjacent to the carbonyl carbon.
Hydrogen atoms attached the these carbons denoted with Greek letters will have the same designation, so an alpha hydrogen is attached to an alpha carbon.
Aldehyde hydrogens not given Greek leters.
α hydrogens display unusual acidity, due to the resonance stabilization of the carbanion conjugate base, called an enolate.
Tautomers are readily interconverted constitutional isomers, usually distinguished by a different location for an atom or a group, which is different than resonance.
The tautomerization in this chapter focuses on the carbonyl group with alpha hydrogen, which undergo keto-enol tautomerism.
Keto refers to the tautomer containing the carbonyl while enol implies a double bond and a hydroxyl group present in the tautomer.
The keto-enol tautomerization equilibrium is dependent on stabilization factors of both the keto tautomer and the enol tautomer, though the keto form is typically favored for simple carbonyl compounds.
The 1,3 arrangement of two carbonyl groups can work synergistically to stabilize the enol tautomer, increasing the amount present at equilibrium.
The positioning of the carbonyl groups in the 1,3 arrangement allows for the formation of a stabilizing intramolecular hydrogen bond between the hydroxyl group of the enol and the carbonyl oxygen as well as the alkene group of the enol tautomer is also conjugated with the carbonyl double bond which provides additional stabilization.
Aromaticity can also stabilize the enol tautomer over the keto tautomer.
Under neutral conditions, the tautomerization is slow, but both acid and base catalysts can be utilized to speed the reaction up.
Biological enol forming reactions use isomerase enzymes to catalyze the shifting of a carbonyl group in sugar molecules, often converting between a ketose and an aldose in a process called carbonyl isomerization.
CAN HF USED TO CLEAVE ETHERS EXPLAIN
Answer:
no
Explanation:
Fluoride is not nucleophilic (having the tendency to donate electrons) enough to allow for the use of HF to cleave ethers in protic media(protic solvents are polar liquid compounds that have dissociable hydrogen atoms). The rate of reaction is comparably low, so that heating of the reaction mixture is required.
Identify each of the following half-reactions as either an oxidation half-reaction or a reduction half-reaction.
half-reaction identification
Cu+(aq)--->Cu2+(aq) + e- _________
I2(s) + 2e--->2I-(aq) _________
Answer:
Cu+(aq)--->Cu2+(aq) + e- : oxidation
reason: there is loss of electrons.
I2(s) + 2e--->2I-(aq) : reduction
reason: There is reduction of electrons.
