Answer:
21.2 g
Explanation:
Step 1: Given data
Molar concentration of the solution (C): 0.400 mol/LVolume of solution (V): 500 mL (0.500 L)Step 2: Calculate the moles of Na₂CO₃ (solute) in the solution
We will use the definition of molarity.
C = moles of solute / liters of solution
moles of solute = C × liters of solution
moles of solute = 0.400 mol/L × 0.500 L = 0.200 mol
Step 3: Calculate the mass corresponding to 0.200 moles of Na₂CO₃
The molar mass of Na₂CO₃ is 105.99 g/mol.
0.200 mol × 105.99 g/mol = 21.2 g
La función de la levadura en quimica
Explanation:
las levaduras son pequeños organismos unicelulares que se alimentan de azúcares simples y los descomponen en dióxido de carbono, alcohol (etanol, específicamente), moléculas de sabor y energía. El proceso se conoce como fermentación.
Phosphate buffers are commonly used in biological research. If a small amount of strong acid is added to a buffer solution that is 0.700 M H3PO4 and 0.700 M KH2PO4, which of the following statements is true?
A) [H3PO4] will increase, [KH2PO4] will decrease, and pH will slightly decrease.
B) [H3PO4] will increase, [KH2PO4] will decrease, and pH will not change.
C) [H3PO4] will decrease, [KH2PO4] will increase, and pH will slightly decrease.
D) [H3PO4] will decrease, [KH2PO4] will increase, and pH will slightly increase.
E) [H3PO4] will increase, [KH2PO4] will decrease, and pH will slightly increase.
F) [H3PO4] will decrease, [KH2PO4] will increase, and pH will not change
Answer:
A) [H3PO4] will increase, [KH2PO4] will decrease, and pH will slightly decrease.
Explanation:
A buffer is a solution which resists changes to its pH when a small amount of acid or base is added to it.
Buffers consist of a weak acid (HA) and its conjugate base (A–) or a weak base and its conjugate acid. Weak acids and bases do not completely dissociate in water, and instead exist in solution as an equilibrium of dissociated and undissociated species. When a small quantity of a strong acid is added to a buffer solution, the conjugate base, A-, reacts with the hydrogen ions from the added acid to form the weak acid and a salt thereby removing the extra hydrogen ions from the solution and keeping the pH of the solution fairly constant. On the other hand, if a small quantity of a strong base is added to the buffer solution, the weak acid dissociates further to release hydrogen ions which then react with the hydroxide ions of the added base to form water and the conjugate base.
For example, if a small amount of strong acid is added to a buffer solution that is 0.700 M H3PO4 and 0.700 M KH2PO4, the following reaction is obtained:
KH₂PO₄ + H+ ----> K+ + H₃PO₄
Therefore, [H₃PO₄] will increase, [KH₂PO₄] will decrease, and pH will slightly decrease.:
Acetylide ions react with aldehydes and ketones to give alcohol addition products.
a. True
b. False
Answer:
a
Explanation:
A straight chain hydrocarbon with the formula C5H8_____
Answer:
I has 2 double carbon carbon bonds
If 4.00 moles of O2 occupies a volume of 5.0 L at a particular temperature and pressure, what volume will 3.00 moles of oxygen gas occupy under the same condition?
Answer: Volume occupied by 3.00 moles of oxygen gas under the same condition is 3.75 L.
Explanation:
Given: [tex]n_{1}[/tex] = 4.00 moles, [tex]V_{1}[/tex] = 5.0 L
[tex]n_{2}[/tex] = 3.00 moles, [tex]V_{2}[/tex] = ?
Formula used is as follows.
[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}[/tex]
Substitute the values into above formula as follows.
[tex]\frac{V_{1}}{n_{1}} = \frac{V_{2}}{n_{2}}\\\frac{5.0 L}{4.00 mol} = \frac{V_{2}}{3.00 mol}\\V_{2} = 3.75 L[/tex]
Thus, we can conclude that volume occupied by 3.00 moles of oxygen gas under the same condition is 3.75 L.
Based on your knowledge of factors affecting the rate of reaction, why is there a danger of explosions in places such as flour mills and coal mines where there are large quantities of powdered, combustible materials? 
What is the meaning of beaker?
Answer:
a lipped cylindrical glass container for laboratory use
Explanation:
Can someone help me with this one
Answer:
Easy my dude let me help you out
A.In
B.27
C.73
D.49
E.56
F.56
G.114
H.180
Also with protons and electrons they equal the same atomic number
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.
A student is making a solution of sodium carbonate (Na2CO3) they mix 0.79 grams of sodium carbonate into 50.0 mL of water. What is the molarity of the sodium carbonate solution?
A 0.15 M Na2CO3
B 1.5 x 10^-4 M Na2CO3
C 6.7 M Na2CO3
D 15.8 M NaCO3
Answer:
[Na₂CO₃] = 0.15 M
Explanation:
Molarity is a type of concentration.
It is useful for solutions, to say how many moles of solute are contained in 1L of solution.
We can also say, that molarity are the mmoles of solute in 1 mL of solution.
In this case, our solute is the Na₂CO₃.
We convert mass to moles: 0.79 g . 1 mol / 106g = 7.45×10⁻³ moles
We convert moles to mmoles: 7.45×10⁻³ mol . 1000 mmol / 1mol = 7.45 mmol
M = mmol / mL
M = 7.45 mmol / 50 mL = 0.15 M
Option A is the right answer.
At a constant temperature of 30 °C, an ideal gas occupies 2.78 Liters at a pressure of 1.27 atm. What will be the volume (L) at a pressure of 3.95 atm?
Answer:
[tex]V_2=0.894L[/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 Boyle's law for an inversely proportional relationship between pressure and volume at constant temperature, as described in the problem statement:
[tex]P_2V_2=P_1V_1[/tex]
Thus, we solve for V2, final volume, to obtain the following result:
[tex]V_2=\frac{P_1V_1}{P_2} \\\\V_2=\frac{1.27atm*2.78L}{3.95atm}\\\\V_2=0.894L[/tex]
Regards!
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?
Answer:
12
Explanation:
nNaCl= 4x3=12
Which of the following releases chemical energy?
A. throwing a basketball
B. a skier on top of a muntain
C. playing a song through headphones
D. burning wood
Answer:
D. burning wood
Explanation: It seems like the only logical answer
Tn chemical reaction, the energy is released is called as chemical energy. The burning wood releases the chemical energy. Therefore, option D is correct.
What is chemical energy ?Chemical energy is the energy that is released when chemical substances engage in a chemical reaction and change into other substances. Batteries, food, and gas are a few examples of chemical energy storage mediums.
Chemical energy, such as that held in the bonds of atoms and molecules, is stored energy. As a result of a chemical process, this energy is released. A substance typically changes into an entirely different substance once its chemical energy has been released.
The body transforms the energy in meals into heat and mechanical energy. Additionally, coal's chemical energy is transformed into electrical energy in power plants. Last but not least, electrolysis is another way that the chemical energy in a battery might generate electricity.
Thus, option D is correct.
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a) If we have a 4.5 L container of CH 10 gas at a temperature of 178 K and a pressure of 0.50 atm, then how many moles of CaHio do
we have?
b) How many grams of C4H1o do we have?
Answer:
a) 0.15 mol.
b) 8.95 g.
Explanation:
Hello there!
In this case, according to the given information, it is possible for us to infer this problem is solved by using the ideal gas equation:
[tex]PV=nRT[/tex]
And proceed as follows:
a) Here, we solve for the moles, n, as follows:
[tex]n=\frac{PV}{RT} \\\\n=\frac{0.50atm*4.5L}{0.08206\frac{atm*L}{mol*K}*178K} \\\\n=0.15mol[/tex]
b) for the calculation of the mass, we recall the molar mass of butane, 58.12 g/mol, to obtain:
[tex]0.15mol*\frac{58.12g}{1mol} =8.95g[/tex]
Regards!
Atoms are found to move from one lattice position to another at the rate of 300,000 jumps/s at 500 0C when the activation energy for their movement is 10,000 cal/mol. Calculate the jump rate at 400 0C.
Answer:
1
Explanation:
1
At a fixed volume, a four-fold increase in the temperature of a gas will lead to _______ in pressure.
Question 2 options:
A)
no change
B)
a two-fold decrease
C)
a four-fold decrease
D)
a four-fold increase
Answer:
D) a four-fold increase
Explanation:
According to Gay-Lussac's law, which states that the pressure of a given amount of gas is directly proportional to the temperature at a constant volume, the pressure increases with an increase in temperature.
According to this question, at a fixed volume, a four-fold increase in the temperature of a gas will lead to a four-fold increase in the pressure as well.
You dissolve 14 g of Mg(NO3)2 in water and dilute to
750 mL. What is the molarity of this solution?
Answer:
0.127M
Explanation:
Molarity of a solution = number of moles (n) ÷ volume (V)
Molar mass of Mg(NO3)2 = 24 + (14 + 16(3)}2
= 24 + {14 + 48}2
= 24 + 124
= 148g/mol
Using the formula, mole = mass/molar mass, to convert mass of Mg(NO3)2 to mole
mole = 14g ÷ 148g/mol
mole = 0.095mol
Volume = 750mL = 750/1000 = 0.75L
Molarity = 0.095mol ÷ 0.75L
Molarity = 0.127M
Obtain 2 test tubes. 2. Add 2 mL of animal blood plasma into the first test tube a. Use a pH test strip to measure the pH of the blood plasma. ______
Answer:
7.4
Explanation:
Plasma proteins are part of the buffer systems of blood plasma. Plasma contains both positively and negatively charged amino and carboxyl groups. These compounds' charged portions can attract and link hydrogen(H) and hydroxyl ions(OH-), therefore act as buffers.
Plasma serves as a weak and ineffective buffer. The pH of a buffer should always be around 7.4 which is nearly neutral. As such we may deduce from the first experimental observation that there is no change in pH.
If we have 1.23 mol of NaOH in solution and 0.85 mol of Cl2 gas is available to react, which one is the limiting reactant? Give your reason.
Answer:
NaOH is the limiting reactant.
Explanation:
Hello there!
In this case, since the reaction taking place between sodium hydroxide and chlorine has is:
[tex]NaOH+Cl_2\rightarrow NaCl+NaClO+H_2O[/tex]
Which must be balanced according to the law of conservation of mass:
[tex]2NaOH+Cl_2\rightarrow NaCl+NaClO+H_2O[/tex]
Whereas there is a 2:1 mole ratio of NaOH to Cl2, which means that the moles of the former that are consumed by 0.85 moles of the latter are:
[tex]n_{NaOH}=0.85molCl_2*\frac{2molNaOH}{1molCl_2}\\\\n_{ NaOH}=1.7molNaOH[/tex]
Therefore, since we just have 1.23 moles out of 1.70 moles of NaOH, we infer this is the limiting reactant.
Regards!
Excess HCl is added to 234 g of Na2S solution as shown by the equation below:
Na2S(aq) + 2HCl(aq) →2NaCl(aq) + H2S(g)
How many liters of H2S gas are produced at standard temperature and pressure (STP)? The molar mass of Na2S is 78 g.
Answer:
67 L
Explanation:
Step 1: Write the balanced equation
Na₂S(aq) + 2 HCl(aq) → 2 NaCl(aq) + H₂S(g)
Step 2: Calculate the moles corresponding to 234 g of Na₂S
The molar mass of Na₂S is 78 g/mol.
234 g × 1 mol/78 g = 3.0 mol
Step 3: Calculate the moles of H₂S produced from 3.0 moles of Na₂S
The molar ratio of Na₂S to H₂S is 1:1. The moles of H₂S formed are 1/1 × 3.0 mol = 3.0 mol.
Step 4: Calculate the volume occupied by 3.0 moles of H₂S at STP
At STP, 1 mole of H₂S occupies 22.4 L.
3.0 L × 22.4 L/1 mol = 67 L
g The activation energy for diffusion depends on the strength of atomic bonds. Higher strength bonds result in higher activation energies. How do you predict the activation energy for self diffusion will be related to melting temperature
Answer:
Yes, the activation energy for self diffusion is related to melting temperature.
Explanation:
The activation energy for self diffusion is related to melting temperature because bonds result due to activation energies and we know that bonds are break down when the temperature is increases and as a result the solid substance melts and change into liquid state. When the bonds between atoms are broken down with the use of heat energy the state of matter changes so we can say that activation energy is related to temperature.
define molecular formula?
A molecular formula is an expression that states the number and type of atoms present in a molecule of a substance.
Example : H2O (water) There are 2 atoms of Hydrogen and 1 atom of Oxygen in this substance
Chemosynthesis and photosynthesis are both processes that produce food.
True or false?
Answer:
true
Explanation:
probably true
Imagine a unit of charge called the zorg. A chemist performsthe oil drop experiment and measures the charge of each drop inzorgs. Based on the results below, what is the charge of theelectron in zorgs (z)? How many electrons are in eachdrop?
Drop # Charge
A -4.8 x 10^-9 z
B -9.6 x 10^-9 z
C -6.4 x 10^-9 z
D -12.8 x 10^9z
Answer:
-1.6 × 10⁻⁹ z
Explanation:
To attempt this type of question, we need to first divide each charge present in the question with the smallest one.
i.e.
[tex]A = \dfrac{-4.8 \times 10^{-9}}{-4.8 \times 10^{-9}}= 1[/tex]
[tex]B = \dfrac{-9.6 \times 10^{-9}}{-4.8 \times 10^{-9}}= 2[/tex]
[tex]C= \dfrac{-6.4 \times 10^{-9}}{-4.8 \times 10^{-9}}= 1.33[/tex]
[tex]D= \dfrac{-12.8 \times 10^{-9}}{-4.8 \times 10^{-9}}= 2.67 \simeq 3[/tex]
The next thing to do is to multiply each obtained value with the highest integer
A = 1 × 3 = 3
B = 2 × 3 = 6
C = 1.33 × 3 = 3.99
D = 3 × 3 = 9
Finally, we divide each charge by the result from above.
[tex]A = \dfrac{-4.8 \times 10^{-9}}{3}= -1.6 \times 10^{-9}[/tex]
[tex]B = \dfrac{-9.6 \times 10^{-9}}{6}= -1.6\times 10^{-9}[/tex]
[tex]C= \dfrac{-6.4 \times 10^{-9}}{3.99}= -1.6\times 10^{-9}[/tex]
Thus, we can therefore easily conclude that the charge in zorgs (z) is:
-1.6 × 10⁻⁹ z
What is the mass in grams of 0.700 moles of water, H2O
Answer:
12.6
Explanation:
[tex]no \: of \: mole= \frac{mass}{molar \: mass} [/tex]
0.7=mass/(2+16)
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 12.6g is the mass in grams of 0.700 moles of water.
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number. The stoichiometry represents the number of moles.
Mathematically,
number of moles of water=given mass of water÷ molar mass of water
Molar mass of 1 mole of water= 18 g/mol
mass of water= ?
0.700 moles=moles of water
Substituting all the given values in the above equation, we get
0.700 moles=mass of water ÷ 18 g/mol
mass of water =12.6g
Therefore, 12.6g is the mass in grams of 0.700 moles of water.
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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:
The information below describes a redox reaction.
Ag+ (aq) + Al(s) — Ag(s) + Al3+ (aq)
Ag+ (aq) + -> Ag(s)
Al(s)->A3+ (aq) + 3e-
What is the coefficient of silver in the final, balanced equation for this reaction?
Answer:
Al°(s) + 3Ag⁺(aq) => Al⁺³(aq) + 3Ag(s)
Explanation:
Oxidation: Al°(s) => Al⁺³(aq) + 3e⁻
Reduction: 3Ag⁺(aq) + 3e⁻ => 3Ag°(s)
_________________________________________
Net Rxn: Al°(s) + 3Ag⁺(aq) => Al⁺³(aq) + 3Ag(s)
One mole of neutral aluminum atoms (Al°(s)) undergo oxidation delivering 3 moles of electrons to 3 moles silver ions (3Ag⁺³(aq)) that are reduced to 3 moles of neutral silver atoms (3Ag°(s)) in basic standard state 25°C; 1atm.
A balanced equation obeys the law of conservation of mass. According to the law of conservation of mass, mass can neither be created nor be destroyed. The coefficient of silver is 3.
What is a balanced equation?A balanced chemical equation can be defined as the chemical equation in which the number of reactants and products on both sides of the equation are equal. The amount of reactants and products on both sides of the equation will be equal in a balanced chemical equation.
The numbers which are used to balance the chemical equation are called the coefficients. The coefficients are the numbers which are added in front of the formula.
The balanced chemical equation for the given redox reaction is given as:
Al (s) + 3 Ag⁺ (aq) → Al³⁺ (aq) + 3Ag (s)
Thus the coefficient of silver is 3.
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Which subatomic particles each have a mass of approximately 1 u?
A)
proton and electron
B)
proton and neutron
C)
neutron and electron
D)
neutron and positron
Answer:
be is the answer to your question
For the equilibrium that exists in an aqueous solution of nitrous acid (HNO2, a weak acid), the equilibrium constant expression is: _________
a. K = [ H+] [NO2-] / [HNO2]
b. K = [ H+] [N] [O]2 / [HNO2]
c. K = [ H+] [NO2-] / [HNO2]
d. K = [H+]2 [NO2-] / [HNO2]
e. None of these
Answer: For the equilibrium that exists in an aqueous solution of nitrous acid (HNO2, a weak acid), the equilibrium constant expression is K = [ H+] [NO2-] / [HNO2].
Explanation:
An expression that depicts the ratio of products and reactants raised to the power of their coefficients at equilibrium is called equilibrium constant.
An equilibrium constant is denoted by the symbol 'K'.
For example, the dissociation of nitrous acid in aqueous solution is as follows.
[tex]HNO_{2} \rightleftharpoons H^{+} + NO^{-}_{2}[/tex]
Hence, its expression for equilibrium constant is as follows.
[tex]K = \frac{[H^{+}][NO^{-}_{2}]}{[HNO_{2}]}[/tex]
Thus, we can conclude that for the equilibrium that exists in an aqueous solution of nitrous acid (HNO2, a weak acid), the equilibrium constant expression is K = [ H+] [NO2-] / [HNO2].
4. Complete the following equations:
CuCl2 + Na2CO3 → 2 NaCl +............
FeSO4 + BaCl2 →
Cu(NO3)2 + CaCO3
Answer:
2NaCl + CuCO3
FeCl2 + BaSO4
CuCO3 + Ca(NO3)2
Explanation:
Presumably this is a double replacement reaction.
A+B + C+D → A+D + C+B
It seems I may be wrong so please try to work out the problem yourself to double check, keeping in mind the charges of each compound.
