Answer:
d.) 1.0 M HNO2, 1.0 M NaNO2
Explanation:
A buffer is a mixture that is capable of tolerating addition of a strong acid or base without altering the pH substantially.
A buffer is the mixture of a WEAK ACID AND ITS CONJUGATE BASE or a WEAK BASE AND ITS CONJUGATE ACID
In the problems:
a) HCl is a strong acid and NaCl a salt. NO buffer
b) NH3 is a weak base and NaCL a salt. NO buffer
c) HF is a weak acid and NaCl a salt. NO buffer.
d) HNO2 is a weak acid and NaNO2 its conjugate base. A BUFFERPLEASE HELP
If I put more air in a car tire, which relationship does it show?
a. pressure and volume
b. temperature and volume
c. amount of gas and pressure
Selected: d. temperature and pressure
Answer:
amount of gas and pressure
How many moles of CO2 are there in 2.55E18 molecules of CO2?
Answer: 1.535e42 (or 1.535x10^42) moles of CO2
Explanation: i know this is six days late, but all you have to do for this one is multiply 2.55e18 by the standard mole value, 6.02e23 and your calculator will give you 1.535e42 moles!
What is the iupac name of CH3-CH2-CH2-OH?
Answer:
the iupac name of CH3-CH2-CH2-OH Propanol.
What part of the US government continued to study cold fusion after others gave up on it?
A.) the Army
B.) the Navy
C) the Coast Guard
D.) the Marines.
what is a major disadvantage of crude oil as an energy resource ?
Answer:
Burning oil can pollute the air. Much of our oil has to be imported and it is becoming more and more expensive as reserves reduce and imports increase. Producing electricity from crude oil is expensive compared to other fossil fuels such as coal or gas.
Explanation:
If sufficient acid is used to react completely
with 21.0 grams of Mg
Mg(s) + 2 HCl(aq) + MgCl2(aq) + H2(g)
what volume of hydrogen at STP would be
produced?
1. 9.68 liters
2. 10.60 liters
3. 4.84 liters
4. 19.37 liters
5. 22.40 liters
Solution,
Mass of Mg - 21gm
molar mass of Mg - 24gm
moles = Given mass/ Molar mass
moles = 21/24 = 0.875
1 mole of Mg produce 1 mole of H2 gas
so 0.875 mole of Mg will produce 0.875 moles of H2 gas
One mole of H2 gas = 22.4 litre
0.875 mole of H2 gas = 0.875×22.4
0.875 mole of H2 gas = 19.60 litre
So the nearest ANSWER is Option four 19.37 litre.
STP is the standard temperature and the pressure of the gases of the system. The volume of the hydrogen that will be produced as STP is 19.37 litres.
What is volume?Volume is the amount of the substance or the solution occupied in an area or object and is estimated in L or mL. It is a scalar quantity.
Given,
Mass of magnesium = 21 gm
Molar mass of magnesium = 24 gm/mol
Moles of magnesium can be calculated as,
[tex]\begin{aligned}\rm moles &= \rm \dfrac{mass}{molar\;mass}\\\\&= \dfrac{21}{24}\\\\&= 0.875 \;\rm mol\end{aligned}[/tex]
If 1-mole magnesium = 1-mole hydrogen gas
Then 0.875-mole magnesium = 0.875 moles of hydrogen gas
If 1 mole of hydrogen gas = 22.4 L
Then, 0.875 moles of hydrogen gas = x L
Solving for x:
[tex]\begin{aligned}\rm x &= 0.875 \times 22.4\\\\&= 19.60 \;\rm litre\end {aligned}[/tex]
Therefore, the volume of hydrogen at STP would be option 4. 19.37 litres.
Learn more about volume and STP here:
https://brainly.com/question/1323332
As you move down and to the left on the periodic table metals become a
Name a substance which will undergo changes from solid to liquid to gas between 0c and 100c
Answer:
WATER
Explanation:
Water melting point 0 c boiling 100c
On the calendar provided below, the full moon is shown happening on the eleventh of the month? What moon would you see around the 25th of the month, shown with the question mark? Question 8 options: A. First Quarter B. New Moon C. Waxing Crescent D. Waning Gibbous
Answer:
The correct answer is - B. New Moon.
Explanation:
The change of moon disc from all black to all light to all dark again is called the lunar cycle. It takes almost 30 days (29.53059 to be precise). The time from all black to all light or all light to all black is almost 15 days. All black moon is termed as the new moon and all light is termed as the full moon.
As given that the full moon is shown happening on the eleventh of the month then what moon would be around 25 which is 14 days later that should be in waxing gibbous phase and almost new moon.
Thus, the correct answer is - B. new moon.
GUYS, PLEASE HELP ME I'M ON THE LAST QUESTION AND I GET IT WRONG I HAVE TO START OVER. no links
Answer:
its actually experimental this time
Explanation:
sorry bout the last one i just wanna help:(
What is a single-displacement reaction?
a type of reaction that occurs when two simple substances interact to form a single new, more complex compound
a type of reaction that occurs when a single substance breaks down into two or more less complex substances
a chemical reaction that occurs when a substance combines with molecular oxygen, releasing light and heat
a chemical reaction that occurs when one element within a compound is exchanged with another element
Answer:
it's the last one.
Explanation:
a compound reaction that occurs when one element within a compound is exchanged with another element.
A student added 3 gms one substance in a beaker and then added 4 gms of another substance. A chemical reaction took place in the uncovered beaker, after the reaction the beaker weighed 5 gms which of the following is the best explanation?
A Some of the mass of the reactants was lost as heat and evaporated into the air.
B. The reaction produce a gas as a product.
C. Some of the reactantants were destroyed as when the chemicals were added.
Answer:
B. The reaction produce a gas as a product.
Explanation:
According to the law of conservation of mass, the total mass of reactants must be equal to the total mass of products because mass is neither created nor destroyed in a chemical reaction.
The total mass of the reactants is 7 grams. The total mass of the products and the beaker is 5 grams. This means that the mass of products is less than the mass of reactants.
The only plausible explanation for this is that the reaction produced a gaseous product which escaped because the system is an open system thereby leading to a lesser measured mass of products since mass can not be created nor destroyed.
Given the information in the velocity vs. time graph,
what is the displacement of the object after 1 second?
After 3 seconds?
After 5 seconds?
aniapsmxuansyxineydo
What is cells function of animal cell??
PLZ HELP ME
Answer:
Controls the movement of substances into and out of the cell.
Mg + 2HCl → MgCl2 + H2
How many grams of hydrochloric acid (HCI) is needed to produce 200g of H2?
Answer:
7242.1g
Explanation:
The balanced equation for this reaction is as follows:
Mg + 2HCl → MgCl2 + H2
From the above equation, it can be observed that 2 moles of HCl is needed to produce 1 mole of H2.
Using the formula below, we convert the mass of H2 to moles;
Molar mass of H2 = 2.016g/mol
mole = 200/2.016
mole = 99.21mol of H2
Since 2 moles of HCl is needed to produce 1 mole of H2.
Then 99.21 moles of H2 will be produced by 99.21 × 2 = 198.4mol of HCl
Molar mass of HCl = 1 + 35.5
= 36.5g/mol
Mole = mass/molar mass
Mass = molar mass × mole
Mass = 36.5 × 198.4
Mass = 7242.1g
How many calories are absorbed in a process that absorbs 0.128 joules?
A. 0.031 cal
B. 0.536 cal
C. 536 cal
D. 0.310 cal
You have a mixture that contains 0.380 moles of Ne(g), 0.250 moles of He(g), and 0.500 moles CH4(g) at 400 K and 6.25 atm. What is the partial pressure of He?
Answer:
1.38 atm
Explanation:
Partial pressure of a gas = total pressure × mole fraction of that gas.
Mole fraction of a gas is moles of a gas ÷ total moles of all gases.
The partial pressure of Helium gas is 2.756 atm. This can be calculated by using mol fraction first.
Calculation of mol fraction:
It is the ratio of one mole of gas to the total moles of all the gases.
Total moles of all gases = 0.380+0.250+0.500 =1.13
Mol fraction of Helium gas = 0.500/1.13
Mol fraction of Helium gas = 0.442
Calculation of partial pressure:It is the product of mol fraction of the gas to the total pressure given.
Partial pressure= 0.442 * 6.52 atm
Partial pressure=2.765 atm
Find more information about Mol fraction here:
brainly.com/question/1601411
Which type of pressure system is located near Seattle? *
Answer:
Seattle is shielded from extreme weather by the Cascade and Olympic mountain regions to the east and west, respectively. Low pressure systems tend to come from the south while high pressure systems tend to come from the north.
6.
What are the mass numbers of; hydrogen, helium
and boron? I
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At STP 101.3 kPa 0 C one mole of Ar gas was collected and was found to occupy a volume of 22.4L What is the value of the gas constant in rounded to the nearest hundredth?
Answer:
8.31 KPa.L/Kmol
Explanation:
From the question given above, the following data were obtained:
Pressure = 101.3 KPa
Temperature (T) = 0 °C = 273 K
Number of mole (n) = 1 mole
Volume = 22.4 L
Gas constant (R) =?
The gas constant can be obtained as follow:
PV = nRT
101.3 × 22.4 = 1 × R × 273
2269.12 = R × 273
Divide both side by 273
R = 2269.12 / 273
R = 8.31 KPa.L/Kmol
Therefore, the value of the gas constant is 8.31 KPa.L/Kmol
18.) CCC Energy and Matter Photovoltaic power from solar panels and biomass
energy are obviously forms of solar energy, coming from sunlight. Explain why
both wind power and hydroelectric power can also be considered to be forms of
solar energy.
Answer:
See Explanation
Explanation:
Renewable energy sources refers to those energy sources that can never be depleted. This means that they can be used severally without getting exhausted. Solar, biomass, wind and hydroelectric power are all renewable energy sources.
Hence, from the perspective described above, we can say that wind is a form of solar energy because wind is formed when the air is heated by the sun.
Hydroelectric power is driven by the water cycle. This water cycle somehow depends on the sun to run efficiently. So, hydroelectric power can also be considered to be a form of solar energy.
How many atoms are in 0.500mol of calcium?
Answer:
3.01×10²³ atoms of calcium
Explanation:
number of moles = number of atoms/Avogadro's constant
n = N/NA
N = n×NA = 0.500 mol×6.02×10²³ mol^-1
N = 3.01×10²³ atoms of calcium
1 Which process causes the greatest increase in the distance between particles?
A condensation
B freezing
C melting
D sublimation
The Answer is compensation
This diagram illustrates the life cycle of a tomato plant. Which stage in this plant life cycle is the adult? Tomato Plant Life Cycle
Answer:
the answer is A
Explanation:
hope it hlp
(PLEASE HELP) 500 mL of a gas is collected at 745 mmHg. What will the volume be at 1.8 atm?
Answer:
272.22 mLExplanation:
The new volume can be found by using the formula for Boyle's law which is
[tex]P_1V_1 = P_2V_2[/tex]
where
P1 is the initial pressure
P2 is the final pressure
V1 is the initial volume
V2 is the final volume
Since we're finding the new volume we have
[tex]V_2 = \frac{P_1V_1}{P_2} \\[/tex]
First convert 745 mmHg to atm
760 mmHg = 1 atm
745 mmHg = 745/760 = 0.98 atm
We have
[tex]V_2 = \frac{500 \times 0.98}{1.8} \\ = 272.222...[/tex]
We have the final answer as
272.22 mLHope this helps you
Which of the following describes an impact of the specific heat of water on the planet and the life forms that exist on it?
a) places near the sea show high high temp variation
b) inland cities have moderate temperatures throughout the year
c) marine life experiences sudden spikes and drops in temperature
d) sweat requires a lot of thermal energy to be absorbed to evaporate
Answer:
The answer is D, "sweat requires a lot of thermal energy to be absorbed to evaporate."
Explanation:
Like the other person, I just took the test.
An impact of the specific heat of water on the planet and the life forms in it is: D. sweat requires a lot of thermal energy to be absorbed to evaporate.
What is thermal energy?Thermal energy is also referred to as heat and it can be defined as a form of energy that is transferred from one physical object to another, especially due to a difference in temperature.
Generally, a lot of thermal energy is required to be absorbed for sweat to evaporate and this is mainly due to the impact of specific heat of water on the planet and all the life forms that are existing on it.
Read more on thermal energy here: brainly.com/question/12072129
Given the formula of a compound:
(1) aldehyde
(2) alkene
(3) alkyne
(4) alcohol
Answer:
Number 3 alkyne is the answer
Explanation:
Answer: The answer is Alkyne.
Oxidation, or the loss of electrons, will result in an element becoming _____ positive. This element will show a(n) _____ in oxidation number. Reduction, the gain of electrons, will cause an element to become _____ positive and the element will show a(n) _____ in oxidation number.
Answer:
1)more
2) increase
3)less
4)decrease
Explanation:
Oxidation can be regarded as process involving loss of electrons when a reaction is taking place by an atom or molecule, atom as well as ion. Oxidation do take place as when there is increase in oxidation state of a molecule as well as atom or ion. Reduction which is opposite process takes place as a result of gain in electrons, or when there is decrease in oxidation state of an atom as well as molecule, or ion. Oxidation number gives the the number which is been allocated to elements during a reaction of chemical combination. It gives the count of sharable electrons for an atoms or electron it can gain or loose as chemical bonding is taken place.
It should be noted Oxidation, or the loss of electrons, will result in an element becoming more positive. This element will show an increase in oxidation number. Reduction, the gain of electrons, will cause an element to become less positive and the element will show a decrease in oxidation number.
If there are 3 cats but they each die of different diseases one of heart fail, second of Brian tumor and 3rd of experiment gone wrong, which how many cats are left.
Answer:
none
Explanation:
It is given that there are 3 cats.
Each of the cats die with different diseases. One of cats died due to heart failure, the second cats died because of brain tumor and the third cat died due to an experiment gone wrong.
So there are none of the cats left out. All the cats died due to different reasons.
DUE IN 15 MINS! I just wanna clarify
Answer:
well im sorry to say this but good luck >:}
Explanation: