Answer:
1
Explanation:
1
what are the characteristics of primary standard substances?
Answer:
the characteristics of primary standard substances are:
1.High purity.
2.Stability (low reactivity)
3.Low hygroscopicity
4.High equivalent weight
5.Non-toxicity.
Ready and cheap availability.
During the synthesis of 2,4-dinitrophenylhydrazone derivative, you were instructed to triturate the crude product with 10 mL of 2 M hydrochloric acid. What is the purpose of this trituration
Answer:
to remove any remaining 2,4-dinitrophenylhydrazone
Explanation:
Usually, when an organic compound is synthesised, traces of impurities such as excess reagents or solvent remain in the product.
It is therefore imperative that these contaminants are removed so that the product can attain a very high degree of purity.
Hence, during the synthesis of 2,4-dinitrophenylhydrazone derivative, 10 mL of 2 M hydrochloric acid is titrated against the crude product so that any remaining 2,4-dinitrophenylhydrazone is removed.
what is electron configuration of oxygen in its excited state
Answer:
[tex]1 {s}^{2} 2 {s}^{2} 2 {p}^{4} [/tex]
OR
[tex]2 : 6[/tex]
Answer:
If we look at the ground state (electrons in the energetically lowest available orbital) of oxygen, the electron configuration is [tex]1s^{2} 2s^{2} 2p^{4}[/tex] . If the element were to become excited, the electron could occupy an infinite number of orbitals. However, in most texts, the example will be the next available one. So for oxygen, it might look like this: [tex]1s^{2} 2s^{2} 2p^{3}3s^{1}[/tex] - where the valence electron now occupies the 3s orbital in an excited (i.e. not ground) state.
So, the electron configuration of oxygen in its excited state is [tex]1s^{2} 2s^{2} 2p^{3}3s^{1}[/tex].
Calculate the number of moles of magnesium, chlorine, and oxygen atoms in 3.50 moles of magnesium
perchlorate. Mg(C104)2.
Express the number of moles of Mg, Cl, and O atoms numerically, separated by commas.
Answer:
[tex]n_{Mg}=3.50molMg\\\\ n_{Cl}=7.00molCl\\\\n_O=28.0molO[/tex]
Explanation:
Hello there!
In this case, according to the given information it turns out possible for us to realize that one mole of the given compound, Mg(ClO₄)₂, has one mole of Mg, two moles of Cl and eight moles of O; thus, we proceed as follows:
[tex]n_{Mg}=3.50molMg(ClO_4)_2*\frac{1molMg}{1molMg(ClO_4)_2}=3.50molMg\\\\ n_{Cl}=3.50molMg(ClO_4)_2*\frac{2molCl}{1molMg(ClO_4)_2}=7.00molCl\\\\n_O=3.50molMg(ClO_4)_2*\frac{8molO}{1molMg(ClO_4)_2}=28.0molO[/tex]
Best regards!
Phosphine, PH3, a reactive and poisonous compound, reacts with oxygen as follows: 4PH3(g) 8O2(g) - P4O10(s) 6H2O(g) If you need to make 6.5 moles of P4O10, how many moles of PH3 is required for the reaction
Answer: 26 moles of [tex]PH_3[/tex] are required for the reaction.
Explanation:
We are given:
Moles of [tex]P_4O_{10}[/tex] = 6.5 moles
The given chemical reaction follows:
[tex]4PH_3(g)+8O_2(g)\rightarrow P_4O_{10}(s)+6H_2O(g)[/tex]
By the stoichiometry of the reaction:
If 1 mole of [tex]P_4O_{10}[/tex] is produced by 4 moles of [tex]PH_3[/tex]
So, 6.5 moles of [tex]P_4O_{10}[/tex] will be produced by = [tex]\frac{4}{1}\times 6.5=26mol[/tex] of [tex]PH_3[/tex]
Hence, 26 moles of [tex]PH_3[/tex] are required for the reaction.
Write an equation for the proton transfer reaction that occurs when the following acid reacts with water. Draw curved arrows that show a mechanism for the proton transfer, and modify the given structures to draw the resulting products.
Answer: hello your question has some missing data attached below is the complete question.
answer:
attached below
Explanation:
Attached below is the mechanism for proton transfer
a) HBr
H₃O + Br⁻
b) attached below
c) attached below
Why is specific activity used as a measurement of enzyme purity, but the turnover number cannot be used for this purpose?
Answer:
See explanation
Explanation:
Specific activity of an enzyme is defined as a measure of the rate of reaction between enzyme and substrate.
In the study of enzyme kinetics, specific activity is particularly regarded to be the amount of substrate converted by the enzyme per milligram of protein per unit of time. It is thus a reliable measure of enzyme activity per milligram of total protein.
On the other hand, the turnover number is defined as a measure of the number of conversions achieved by a substrate molecule in one second at a particular active site depending on the specific enzyme concentration.
Since specific activityof the enzyme is the ratio of the enzyme activity to enzyme concentration, then specific activity can be used as a measurement of enzyme purity.
38. Consider the following equilibrium:
2CO(g) + O2(g) =2CO2
Keg=4.0 x 10-10
What is the value of Key for 2CO2(g) + 2COR + O2g) ?
Answer:
[tex]Key=2.5x10^{-9}[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out possible for us to calculate the equilibrium constant value for the reverse reaction:
[tex]2CO_2(g) \rightleftharpoons 2CO(g) + O_2(g)[/tex]
By knowing that the equilibrium expression is actually:
[tex]Key =\frac{[CO]^2[O_2]}{[CO_2]^2} =\frac{1}{Keg}[/tex]
Thus, we plug in and solve for the inverse of Keq to obtain Key as follows:
[tex]Key =\frac{1}{4.0x10^{-10}}\\\\Key=2.5x10^{-9}[/tex]
Regards!
A pressure cooker contains 5.68 L of air at a temperature of 390 4K if the absolute pressure of the air in the pressure cooker is 205 Pa how many moles of air are in the cooker
Answer:
3.59x10⁻⁴ mol
Explanation:
Assuming ideal behaviour we can solve this problem by using the PV=nRT formula, where:
P = 205 PaV = 5.68 Ln = ?R = 8314.46 Pa·L·mol⁻¹·K⁻¹T = 390.4 KWe input the data given by the problem:
205 Pa * 5.68 L = n * 8314.46 Pa·L·mol⁻¹·K⁻¹ * 390.4 KAnd solve for n:
n = 3.59x10⁻⁴ molHELLLLLLLLPPPPPPPPPPPPPPPPPP
Answer:
aa
Explanation:
There is a lowercase a on both sides.
Calculate the number of moles of gas in a basketball inflated to a total pressure of 1.65 atm with a volume of 3.2 L at 250C. ( K = oC + 273)
Answer:
0.123 mol
Explanation:
Step 1: Convert 250 °C to Kelvin
We will use the following expression.
K = °C + 273
K = 250 + 273 = 523 K
Step 2: Calculate the number of moles of gas (n)
A gas occupies a container with volume (V) 3.2 L at a temperature (T) of 523 K and pressure (P) of 1.65 atm. We can calculate the number of moles of the gas using the ideal gas equation.
P × V = n × R × T
n = P × V / R × T
n = 1.65 atm × 3.2 L / (0.0821 atm.L/mol.K) × 523 K = 0.123 mol
Copper sulfate is made of one copper (Cu) atom, one sulfur (S) atom, and four oxygen (O) atoms. Write the chemical formula correctly.
What’s the answers to the answers
Kristy finds the mass of an object to be 20 grams and the volume to be 10 mL. What is the density of the object? (don't send me links, just give a straight answer)
How much energy is used when 14.3 moles of hydrosulfuric acid reacts with 17.1 moles
of oxygen?
2 H2S + 3 02 + 175 KJ
—->2 SO2 + 2 H20
Which substance is the limiting reactant?
Answer:
O2 is the limiting reactant.
Explanation:
Hello there!
In this case, according to the given information about this reaction, one could identify the limiting reactant by performing a mole ratio of H2S to SO2 and O2 to SO2:
[tex]14.3molH_2S*\frac{2molSO_2}{2molH_2S}=14.3molSO_2 \\\\17.1molO_2*\frac{2molSO_2}{3molO_2}=11.4molSO_2[/tex]
Thus, since 17.1 moles of O2 yields fewer moles than 14.3 moles of H2S, we infer the former is the limiting reactant.
Regards!
why hydride ion is strong base than hydroxide ion?
Answer:
The hydride ion,H−is a stronger base, so it will abstract a proton from the water. As the water will give protons, so water will work as an acid and an acid-base reaction will take place. Hydride ions get protons from water and form hydrogen gas and hydroxide ions.
Sodium hydride is the chemical compound with the empirical formula NaH. This alkali metal hydride is primarily used as a strong yet combustible base in organic synthesis. NaH is a saline (salt-like) hydride, composed of Na+ and H− ions, in contrast to molecular hydrides such as borane, methane, ammonia, and water.
Which of the following explains the high boiling
point of water?
a Surface tension
b Polarity
C Capillary action
d Hydrogen bonding
Answer:
The correct answer is - d. hydrogen bonding.
Explanation:
Water has strong hydrogen bonds between its molecules that require a very high amount of energy in order to break. Water molecules are joined together or bound with a strong intermolecular force called hydrogen bonds.
These bonds require more kinetic energy which means more temperature or heat in order to break the bonds and turn into steam and this is the reason it has a high boiling point.
What is the meaning of beaker?
Answer:
a lipped cylindrical glass container for laboratory use
Explanation:
what does the atmoic weight 1 in hydrogen tell scientists
A. pounds hydrogen weighs.
B. protons hydrogen has in its nucleus.
C. other elements hydrogen interacts with.
D. neutrons hydrogen releases in the atmosphere.
Explanation:
The atomic number is equal to the number of protons in an atom's nucleus. Hydrogen's atomic number is 1 because all hydrogen atoms contain exactly one proton.
Write a summary of the science of muscle growth?
Answer:Muscle growth or “skeletal muscle hypertrophy,” as it's called at science parties) is the result of a complex process that adds more myosin “filaments” to each muscle fiber. This makes the “engine” of the cell bigger and stronger over time. ... This process is called muscle protein synthesis, or MPS. Skeletal muscle is composed of thread-like myofibrils and sarcomeres that form a muscle fiber and are the basic units of contraction. The 650 skeletal muscles in the human body contract when they receive signals from motor neurons, which are triggered from a part of the cell called the sarcoplasmic reticulum.
You have 4 litres of a 3.0 mol/L solution of NaCl in a
chemical store room.
How many moles of NaCl are present? *
0.75 mol
1.33 mol
12 mol
M = 3.0 mol/L
V = 4 L
Required:n
Solution:M = n / V
n = MV
n = (3.0 mol/L)(4 L)
n = 12 mol
Therefore, the number of moles of NaCl present is 12 mol.
#ILoveChemistry
#ILoveYouShaina
Answer 12 mol
Explanation: [tex]C_{M} = \frac{n}{V} ==> n = C_{M} *V=4*3=12 mol[/tex]
A mixture of 3 moles of N2, 5 moles of CO2, and 10moles of Cl2 exert a total pressure of 1120 mmHg. What is the partial pressure of CO2?
Answer:
A mixture of 3 moles of N2, 5 moles of CO2, and 10moles of Cl2 exert a total pressure of 1120 mmHg. What is the partial pressure of CO2?
Explanation:
According to Dalton's law of partial pressures:
The partial pressure of a gas can be determined by using the formula:
[tex]the partial pressure of a gas = mole fraction of the gas * total pressure[/tex]
Partial pressure of CO2:
[tex]partial pressure of CO2= total pressure * mole fraction of CO2\\\\Mole fraction of CO2=\frac{number of moles of CO2}{total number of moles of all the gases} \\mole fraction of CO2=\frac{5mol}{3mol+5mol+10mol} = 5/18\\Partial pressure of CO2=\frac{5}{18} * 1120mmHg\\ =311.1mmHg[/tex]
Hence, the partial pressure of CO2 is 311.1mmHg.
A company manufacturing KMnO4 wants to obtain the highest yield possible. Two of their research scientists are working on a technique to increase the yield.
Both scientists started with 50.0 g of manganese oxide (MnO2).
What is the theoretical yield of potassium permanganate when starting with this 50.0 g MnO2?
The equation for the production of potassium permanganate is as follows:
2 MnO2 + 2 KOH + O2 → 2 KMnO4 + H2
You must show all work to receive full credit.
Answer:
[tex]m_{KMnO_4}=90.9gKMnO_4[/tex]
Explanation:
Hello there!
In this case, according to the given chemical equation for the reaction for the production of potassium permanganate, we can see a 2:2 mole ratio of this product to the starting manganese (II) oxide, which means, we can calculate the theoretical yield of the former via stoichiometry:
[tex]m_{KMnO_4}=50.0gMnO_2*\frac{1molMnO_2}{86.94gMnO_2}*\frac{2molKMnO_4}{2molMnO_2} *\frac{158.034gKMnO_4}{1molKMnO_4} \\\\m_{KMnO_4}=90.9gKMnO_4[/tex]
Regards!
The reaction of 9.50 g of carbon with Excess O2 Yield 12.8 of CO2. What is the percent yield of this reaction?
Answer:
Percentage yield = 36.75%
Explanation:
We'll begin by writing the balanced equation for the reaction. This is illustrated below:
C + O₂ —> CO₂
Next, we shall determine the mass of C that reacted and the mass of CO₂ produced from the balanced equation. This can be obtained as follow:
Molar mass of C = 12 g/mol
Mass of C from the balanced equation = 1 × 12 = 13 g
Molar mass of CO₂ = 12 + (2×16)
= 12 + 32
= 44 g/mol
Mass of CO₂ from the balanced equation = 1 × 44 = 44 g
SUMMARY:
From the balanced equation above,
12 g of C reacted to produce 44 g of CO₂.
Next, we shall determine the theoretical yield of CO₂. This can be obtained as follow:
From the balanced equation above,
12 g of C reacted to produce 44 g of CO₂.
Therefore, 9.50 g of C will react to produce = (9.50 × 44) / 12 = 34.83 g of CO₂.
Thus, the theoretical yield of CO₂ is 34.83 g.
Finally, we shall determine the percentage yield of the reaction. This can be obtained as follow:
Actual yield of CO₂ = 12.8
Theoretical yield of CO₂ = 34.83 g
Percentage yield =?
Percentage yield = Actual yield / Theoretical yield × 100
Percentage yield = 12.8 / 34.83 × 100
Percentage yield = 1280 / 34.83
Percentage yield = 36.75%
The dosage for an antibiotic is prescribed at 6.0 mg per kilogram of body weight, taken twice daily for two weeks. What total mass of antibiotic will be taken by a 160-lb person for the two-week period? (1 lb = 454 g)
Answer:
12,096 mg of antibiotics
Explanation:
cuz honeyyy:
160lb=72 kg
6mg twice a day so daily 12mg
12mg per kg so 12×72 =864
for 14 days is :864×14=12,096
Two objects are brought into contact Object 1 has mass 0.76 kg, specific heat capacity 0.87) g'c and initial temperature 52.2 'C. Object #2 has mass 70.7 9. specific heat capacity 3.071" "c' and initial temperature 154 *C. What is the final temperature of the two masses after thermal equilibrium has been reached? Assume the two objects are thermally isolated from everything else. Express your answer in C
Answer:
[tex]T_F=77.4\°C[/tex]
Explanation:
Hello there!
In this case, according to the given information, it turns out possible to set up the following energy equation for both objects 1 and 2:
[tex]Q_1=-Q_2[/tex]
In terms of mass, specific heat and temperature change is:
[tex]m_1C_1(T_F-T_1)=-m_2C_2(T_F-T_2)[/tex]
Now, solve for the final temperature, as follows:
[tex]T_F=\frac{m_1C_1T_1+m_2C_2T_2}{m_1C_1+m_2C_2}[/tex]
Then, plug in the masses, specific heat and temperatures to obtain:
[tex]T_F=\frac{760g*0.87\frac{J}{g\°C} *52.2\°C+70.7g*3.071\frac{J}{g\°C}*154\°C}{760g*0.87\frac{J}{g\°C} +70.7g*3.071\frac{J}{g\°C}} \\\\T_F=77.4\°C[/tex]
Yet, the values do not seem to have been given correctly in the problem, so it'll be convenient for you to recheck them.
Regards!
HELPP
There are 9.23 x 1023 molecules of water in a beaker, how many moles are there?
Answer:
Answer: There are 1.53 moles present in molecules of water in a beaker.
Explanation:
According to the mole concept, there are molecules present in 1 mole of a substance.
So, number of moles present in molecules are calculated as follows.
Thus, we can conclude that there are 1.53 moles present in molecules of water in a beaker.
Explanation:
Which of the following relations is correct for exothermic and endothermic reactions?
Answer:
pa helpppp
Explanation:
pleseee need answerrrr
The correct relations for exothermic and endothermic reactions from the given relations is H Products > H Reactants in exothermic reactions. Hence, Option (D) is Correct.
What is Exothermic Reaction ?
In thermochemistry, an exothermic reaction is a "reaction for which the overall standard enthalpy change ΔH⚬ is negative." Exothermic reactions usually release heat.
Therefore, The correct relations for exothermic and endothermic reactions from the given relations is H Products > H Reactants in exothermic reactions. Hence, Option (D) is Correct.
Learn more about reaction here ;
https://brainly.com/question/17434463
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What is the colour of red cabbage in vinegar?
Answer:
When red cabbage is treated with an acid or a base, it produces anthocyanin, a water-soluble pigment that changes color. In acidic situations with a pH less than 7, the pigment turns red, whereas in alkaline (basic) situations with a pH more than 7, the pigment turns bluish-green.
Explanation:
Classify these bonds as ionic, polar covalent, or nonpolar covalent. You are currently in a sorting module. Turn off browse mode or quick nav, Tab to items, Space or Enter to pick up, Tab to move, Space or Enter to drop. Ionic Polar covalent Nonpolar covalent C-O , Mg-F , Cl-Cl
Answer: The bond present in given compounds is as follows-
Ionic - MgFPolar covalent - CONon-polar covalent - Cl-ClExplanation:
A bond formed due to transfer of electrons from one atom to another is called ionic bond.An ionic bond is always formed between a metal and a non-metal atom.
For example, MgF has metal magnesium and non-metal fluorine. So, an ionic bond is there in the compound MgF.
A compound in which valence electrons are shared between two atoms is called a covalent bond. A covalent bond is always formed between two or more non-metal atoms.When sharing of electrons occur between atoms of different electronegativity then the bond formed is called a polar covalent bond.
For example, C-O has a polar covalent bond.
When sharing of electrons occur between atoms of same element then bond formed is called non-polar covalent bond.For example, Cl-Cl is a non-polar covalent bond.