Answer:
0.000236
Explanation:
Move the decimal point 4 times to the left of its original position
What is the pH at the equivalence point in the titration of 10.0 mL of 0.39 M HZ with 0.200 M NaOH? Ka = 2.4 × 10−6 for HZ.
Answer:
pH = 9.37
Explanation:
The reaction of HZ with NaOH occurs as follows:
HZ + NaOH → H₂O + Na⁺ + Z⁻
When the reaction is in the equivalence point, the moles added of HZ = Moles of NaOH.
At equivalence point, you will have in solution just NaZ that is in equilibrium with water as follows:
Z⁻(aq) + H₂O(l) ⇄ OH⁻(aq) + HZ(aq)
Where K of equilibrium is Kw / Ka = 1x10⁻¹⁴ / 2.4x10⁻⁶ = 4.17x10⁻⁹
And K is defined as:
K = 4.17x10⁻⁹ = [OH⁻] [HZ] / [Z⁻]
To solve this question we must find [Z⁻] and as [OH⁻] and [HZ] comes from the same equilibrium, both are equal and we can find [OH⁻] in order to solve pH:
Moles NaOH added = Moles HZ:
0.010L * (0.39mol / L) = 3.9x10⁻³ moles HZ = Moles NaOH added
The volume of 0.200M NaOH must be:
3.9x10⁻³ moles * (1L / 0.200moles) = 0.0195L.
The moles of HZ = Moles Z⁻ after the reaction and the volume is 0.010L + 0.0195L = 0.0295L. Thus, [Z⁻] is:
[Z⁻] = 3.9x10⁻³ moles / 0.0295L
[Z⁻] = 0.132M
Replacing in K expression:
4.17x10⁻⁹ = [OH⁻] [HZ] / [Z⁻]
4.17x10⁻⁹ = [X] [X] / [0.132]
5.51x10⁻¹⁰ = X²
X = 2.35x10⁻⁵M = [OH⁻]
As pOH = -log [OH⁻]
pOH = 4.63
And pH is
pH = 14 -pOH
pH = 9.37Calcium carbonate + hydrochloric acid forms copper ___ + water + carbon dioxide
What does it form copper what please help me
Answer:
The answer copper carbonate
How many molecules are there in 2.00 moles of ammonia (NH,)?
Answer:
Explanation:
molecules NH3 = 1.47 moles x 6.02x1023 molecules/mole = 8.9x1023 molecules of NH3
Why is it important for the daughter cells to divide a second time in meiosis?
The second division switches parts of matching chromatids to increase genetic variation.
The second division forms four identical cells to ensure that all offspring have the same
The second division sorts chromosomes into cells that are the same as the parent cells.
The second division forms haploid cells that can combine with other haploid cells during fertilization.
Answer:
The second division switches parts of matching chromatids to increase genetic variation.
Explanation:
Meiosis and fertilization create genetic variation by making new combinations of gene variants (alleles).
In a solution, litmus is blue. The pH of the solution could be
1. 10
2. 2
3. 3
4. 4
Answer:
1. 10
Explanation
when litmus paper is blue that means the solution is basic and 10 on the pH scale is the most basic out of all your options
A compound is composed of 53.33%carbon, 11.11%hydrogen and 35.56%oxygen. If the molecular mass of the compound is 90, what is the molecular formula of this compound?
Magnesium bromide is an ionic compound with the chemical formula MgBr2, Magnesium is
Answer:
These are Magnesium bromide is MgBr2. “ionic compounds.” When atoms join together, they form either molecules or ionic compounds, depending on whether they are joined by covalent bonds or ionic bonds. ... When atoms join together by ionic bonds, they form “ionic compounds”.
Explanation:
Hope it helps u
FOLLOW MY ACCOUNT PLS PLS
what happen when a piece of silver metal is added to the copper sulphate solution
Answer:
Explanation:When silver Ag metal is added to copper sulphate CuSO4 solution, no reaction takes place as silver is less reactive than that of copper and cannot displace copper from its solution. Hence, when a piece of silver metal is added to copper sulphate solution there will be no reaction.
Answer:
There will be no reaction
Explanation:
Therefore, when silver Ag metal is added to copper sulphate CuSO4 solution, no reaction takes place as silver is less reactive than that of copper and cannot displace copper from its solution. Hence, when a piece of silver metal is added to copper sulphate solution there will be no reaction.
In an exothermic the change in enthalpy is usually
Positive, because the potential energy of the reactants is higher than the potential energy of the products
Neutral, because the potential energy of the products and reactants cancel each other out.
Negative, because the potential energy of the reactants is higher than the potential energy of the products
Positive, because the potential energy of the reactants is lower than the potential energy of the products
Answer:
Negative, because the potential energy of the reactants is higher than the potential energy of the products
Explanation:
Exothermic reaction is a reaction in which heat is released to surrounding. This is due to the fact that the heat content of the reactant is higher than the heat content of product thus producing a negative enthalpy change (ΔH) i.e
Enthalpy change = Heat of product – Heat of reactant
ΔH = Hp – Hr = negative
Considering the options given in the question above, the correct answer is:
Negative, because the potential energy of the reactants is higher than the potential energy of the products
9) What is the density of the gold rock with a mass of 386 grams and has a volume of 20 cubic centimeters?
O 0.193 g/cc
O 193 g/cc
O 1.93 g/cc
19.3 g/cc
Answer:
density= mass/volume
hence density of gold rock
= 386/20
=19.3 g/cc
HELP !
The provided balanced equation applies to the reaction that takes place between lithium hydroxide and sulfuric acid. 2LiOH + H2SO4 -> Li2SO4 + 2H2O .
If the reaction begins with 26.7 grams of lithium hydroxide (LIOH) and 164.08 grams of suite acid (H2SO4.), how many grams of lithium sulfate (Li2SO4,) is produced? Assume 100% yield . Round your answer to the nearest tenth of a gram .
Answer:
60g or 61.28g
Explanation:
Trust me on this I had the same problem as you
Mr. Whiteman has two stock solutions of sulfuric acid (H2SO4) in the supply closet: 12.1 M and 6.0 M. If he wants to make 10.0 mL of a 1.0 M solution, which stock solution makes more sense to use? Justify with two calculations.
Answer:
12.1-M requires less volume of stock solution.
Explanation:
Hello there!
In this case, according to the foundations of dilution processes, it turns out convenient to remember that the moles of the solute before and after the dilution remains the same; for that reason we use the following equation:
[tex]M_1V_1=M_2V_2[/tex]
Relating the initial and final molarities and volumes. Now, it is seen that V2 is 10.0 mL and M2 is 1.0 M, which means that if we solve for V1 for 12.1 M and 6.0 M, we obtain the following volumes:
[tex]V_1=\frac{M_2V_2}{M_1} \\\\V_1^{12.1M}=\frac{1.0M*10.0 mL}{12.1M}=0.826mL\\\\V_1^{6.0M}=\frac{1.0M*10.0 mL}{6.0M}=1.67mL[/tex]
Therefore, since the 12.1-M solution requires less volume of stock solution, it makes sense to use this one as the initial solution.
Best regards!
What event occurs when the
tension built up along Earth's
plates is released causing one
plate to slip past another?
Answer:
An earthquake
Explanation:
How is matter conserved through cellular respiration
Answer:
In cellular respiration, complex molecules containing carbon react with oxygen to produce carbon dioxide and other materials. ... Matter is conserved during cellular respiration because atoms are conserved in physical and chemical processes
Explanation:
I hope this helps
. If 30.0 grams of copper (II) chloride reacts with 40.0 grams of sodium nitrate, what is the limiting reactant?
Answer:
The limiting reactant is copper (II) chloride
Explanation:
here you go
2NaCl ---> 2Na + Cl2
What are the atoms of the products
Answer: ...
Explanation:
Sodium, chlorine
Answer:
2Na = 2 Sodium [has 2 atoms]
Cl2 = Dichlorine (Chlorine) [has 2 atoms]
Is this what you wanted?? I'm not entirely sure if this is the answer you were looking for.
How
many
moles of water are produced from 12.8 moles of oxygen?
with work
Answer:
12.8 moles
Explanation:
The formula for water is H2O, so for every mole of water, there are two moles of hydrogen and one mole of oxygen.
As the ratio of oxygen particles to water particles is one to one, 12.8 moles of oxygen are required to produce 12.8 moles of water.
Therefore, 12.8 moles of water are produced from 12.8 moles of oxygen (assuming hydrogen is available in excess).
Which change is an environmental effect of destroying wetlands?
loss of habitat
less flooding
smog
acid rain
Answer: Trust me 100% plz its loss of habitat wat they said
Explanation:
Combustion engines became common in the mid-1800s when people began to use them to power ships, trains, and
machinery in factories. Combustion engines add carbon dioxide to the air, and as a result, carbon dioxide in the
atmosphere increased quickly. How did this change the total amount of energy in the Earth system, and how did this
change happen? How did this affect global average temperature?
I need help please and don’t send the fake link): < just to get points
Answer:
The correct answer is - increased the global average temperature.
Explanation:
Combustion is the process that increases the carbon dioxide in the atmosphere, which results in entering more energy into the Earth system than existed from it. Therefore, the amount of energy increased in the system of the earth or surface of the earth.
The reason behind it is that carbon dioxide trapped and redirects energy back toward the Earth's surface, which is absorbed by Earth's surface and surface increased, and global average temperature increased.
Combustion process increases the global average temperature of the earth by absorbing and emitting the energy revert back to earth.
What is combustion?Combustion is a process exothermic process in which organic molecules burns in the presence of oxygen to produce energy in the form of heat and light and CO₂ gas.
CO₂ gas is a green house gas which traps the energy of the atmosphere and revert back it into the earth surface, due to which temperature of the earth surface and atmosphere increases which results in the elevation of global average temperature.
Hence, combustion increases the global average temperature.
To know more about combustion, visit the below link:
https://brainly.com/question/15246277
1.) Magnesium reacts with oxygen and forms magnesium oxide. Write the reaction, and explain how you would find the oxidizing agent
2.) What are two advantages and one disadvantage of fuel cells
3.) How are voltaic and electrolytic cells similar, and how are they different? Include electrodes and their charges in your answer
Answer:
See explanation
Explanation:
1) The reaction of magnesium with oxygen is;
Mg(s) + O2(g) -----> MgO2(s)
The oxidizing agent is the reactant whose oxidation number decreases from left to right in the reaction equation. The oxidation state of oxygen decreased from zero to -2 hence oxygen is the oxidizing agent in the reaction.
2) The advantages of fuel cell includes;
i) it is a clean source of energy
ii) Fuel cells operate quietly and do not constitute noise pollution
One disadvantage of the fuel cell is that its operation is costly.
3) Electrolytic and voltaic cell are similar because they are both electrochemical cells and involve a transfer of electrons between two electrodes.
Electrolytic cells do not operate spontaneously while voltaic cells operate spontaneously. In the volatic cell the anode is negatively charged while the cathode is positively charged. In the electrolytic cell, the anode is positively charged while the cathode is negatively charged.
On a hot day, a student places a glass of cold lemonade on a table outdoors. After a few minutes, water droplets have formed on the outside of the glass.
Is energy absorbed or released by the cold lemonade? Explain your answer.
Compare average kinetic energy for the air molecules and lemonade molecules when the student first places the lemonade outdoors. Explain your answer.
Explain how and why the water droplets form on the outside of the glass.
Answer:
ye but sdfajkd tryng to play me
Explanation:
Answer:
Vapor is released out of the lemonade because when you place it in a hot it will increase.
Explanation:
How many atoms are in 14 moles of I? Watch your significant figures.
A. 8.4 x 10^24 atoms of l
B. 8.43 x 10^24 moles of l
C. 8.4 x 10^23 atoms of I
D. 8.43 atoms of l
Answer:
may be A, 8.43 × 10........ atoms of l
which metal is the most easily oxidized?
A. highly active metal
B. moderately active metal
C.slightly active metal
D.an inactive metal
Answer:
B. Moderately active metal
Explanation:
Commercially available concentrated hydrochloric acid is 37.0% w/w HCl. Its density is 1.18g/ml. Calculate the molarity of concentrated HCl?
Answer:
M = 12.0M
Explanation:
Hello there!
In this case, according to the given by-mass percent of HCl, which can be set up in terms of mass of HCl over mass of solution, we can calculate the molarity, by multiplying by the density to get the mL's of solution and further convert to liters. Moreover, the molar mass of HCl (36.46 g/mol) must be also used to calculate the moles, since molar units requires moles of solute and liters of solution as shown below:
[tex]M=\frac{37.0gHCl}{100g\ sln}*\frac{1.18g\ sln}{1mL\ sln}*\frac{1000mL\ sln}{1L \ sln}*\frac{1molHCl}{36.46gHCl}\\\\M= 12.0M[/tex]
Best regards!
4.What type of energy is used to fuel the process of photosynthesis and what type is produced in
respiration?
A Light energy is used in photosynthesis and created by respiration.
B ATP is used in photosynthesis, which allows the plant to undergo respiration.
C Light energy is used in photosynthesis, whereas respiration creates the energetic product, ATP.
D Food energy is used in photosynthesis and ATP is produced in respiration.
Answer:
A. light energy is used in photosynthesis and created by respiration
What is the best common way to convert fossil fuels into energy?
a. oxidation
b. reaction
c. combustion
d. neutralization
In chemical reactions, the number of atoms in the product is ________________.
A. the same as the number of atoms in the reactants
B. less than the number of atoms in the reactants
C. greater than the number of atoms in the reactants
D. the same as the number of molecules in the reactants
Answer:
A
Explanation:
Pls help really need it pls
Need Help!!
Explain the relationship between volume and temperature (Charles’ Law)
Answer:
the volume of a give gas simple is directly propotional assolute temperature at constant pressure .the volume of a gavi. amount of gass is inversely propotional ot Its pressure when temperature is help constant
what is the scientific method
gn guys I'm finna go now byeee
The scientific method is an empirical method of acquiring knowledge.
These are the 5 scientific methods:
Make observations Ask questionsForm hypothesis make a predictionExamine