Answer:
65.0cp
Explanation:
3
A student has a 5.00 gram sample of calcium chloride (CaCl2) solid. How many moles of calcium chloride are
contained in this sample?
Answer: 0.0450 moles of [tex]CaCl_2[/tex]
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to its molecular mass and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.
To calculate the moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}[/tex]
[tex]\text{Number of moles of} CaCl_2=\frac{5.00g}{110.98g/mol}=0.0450moles[/tex]
Thus there are 0.0450 moles of [tex]CaCl_2[/tex]
The 50:50 mixture of aspirin (Lit. MP: 135-136 oC) and 4-bromobenzoic acid (Lit. MP: 252-254 oC) will have the melting point in the range of:______.
Answer:
193.5-195 °C.
Explanation:
Hello!
In this case, since the mixture is 50:50, we can infer that an average may be used to compute the required range; thus, we first compute the the inner limit by using 135 °C and 252 °C:
[tex]\frac{135+252}{2} =193.5\°C[/tex]
And the upper limit:
[tex]\frac{136+254}{2} =195\°C[/tex]
Thus, the average melting point would be around 193.5-195 °C.
Best regards!
What is the half‑life of an isotope that decays to 25% of its original activity in 85.8 h
Answer:
42.9 h
Explanation:
From the question given above, the following data were obtained:
Original amount (N₀) = 100%
Amount remaining (N) = 25%
Time (t) = 85.8 h
Half-life (t½) =?
Next, we shall determine the number of half-lives that has elapse. This can be obtained as follow:
Original amount (N₀) = 100%
Amount remaining (N) = 25%
Number of half-lives (n) =?
N = 1/2ⁿ × N₀
25 = 1/2ⁿ × 100
Cross multiply
25 × 2ⁿ = 100
Divide both side by 25
2ⁿ = 100/25
2ⁿ = 4
Express 4 index form with 2 as the base
2ⁿ = 2²
n = 2
Thus, two half-lives has elapsed.
Finally, we shall determine the half-life of the of the isotope. This can be obtained as follow:
Time (t) = 85.8 h
Number of half-lives (n) = 2
Half-life (t½) =?
n = t / t½
2 = 85.8 / t½
Cross multiply
2 × t½ = 85.8
Divide both side by 2
t½ = 85.8 / 2
t½ = 42.9 h
Thus, the half-life of the of the isotope is 42.9 h
How many moles of O2 must react to produce .900 mol of NO
Answer:
i dunno
Explanation:
Complex ___ of ETC, which mediates transfer of electrons from succinate (FADH2) to UQ, is not a proton pump.
Answer:
Complex II
Explanation:
Complex II does not directly pump protons but rather sends two protons on to Complex III in the form of the reduced UQ known as ubiquinol.
Thus, the correct answer is Complex II
10 points Part F
Identify at least two limitations of the simulation. How do these limitations influence the
simulation's ability to model the synthesis of ammonia?
Answer and Explanation:
When using simulations, it is important that the researcher knows some limitations. This is because the simulations do not behave exactly like what they represent, in addition to not presenting very important details for analysis and without approximations of what really happens with what they are representing. When modeling the synthesis of Ammonia, for example, these limitations can cause inaccuracies that will compromise the entire analysis.
When using simulations, it is important that the researcher knows some limitations. This is because the simulations do not behave exactly like what they represent, in addition to not presenting very important details for analysis and without approximations of what really happens with what they are representing. When modeling the synthesis of Ammonia, for example, these limitations can cause inaccuracies that will compromise the entire analysis.
Which statement best describes a heart attack?
A. The heart muscle tissues get too much oxygen
B. The heart muscle tissue get too little oxygen
C. The heart muscle tissue get the normal average amount of oxygen
D. None of the above
Answer:
D
Explanation:
Explain how the Octet Rule would say that the elements of potassium and chlorine would react.
Answer:
The octet rule is only applicable to the main group elements. The molecules of the halogens, oxygen, nitrogen, and carbon are known to obey the octet rule. In general, the elements that obey this rule include the s-block elements and the p-block elements (except hydrogen, helium, and lithium).
Explanation:
I hope this helps and pls mark me brainliest :)
Explain why NO is more soluble in water than either N2 or O2. Fill in the following blanks.
a. Compared to nitrogen, the ____________of ethylene makes it more soluble in water.
b. The high solubility of sulfur dioxide can be explained by its ______________
c. Nitric oxide is more soluble than nitrogen and oxygen because of its ______________
d. Compared to oxygen, nitrogen's _____________ makes it more difficult for water molecules to surround the nitrogen molecules.
1. Polarity
2. Ability to react with water
3. Shorter bond length
4. Larger molecular size
Answer:
a. Larger molecular size
b. Ability to react with water
c. Polarity
d. Shorter bond length
Explanation:
Ethene is a larger molecule than oxygen and nitrogen hence it is more soluble than the both other gases .
SO2 dissolves readily in water to yield an acid solution. It is an acid anhydride.
Nitric oxide is a polar compound. It remains very much polar while nitrogen and oxygen are non polar.
Nitrogen is sp hybrized, this leads to a very short bond and does not easily interact with oxygen and nitrogen
Plz help it over science stuff
Answer:9.012
Explanation:
I used the periodic table, the mass is 9.012
Answer:
Pretty sure it would be 69(nice).
Explanation:
You add the number of protons and neutrons to find the mass
You dissolve 0.64 g of potassium chloride (KCl) in 725 ml of water.
What is the molarity of the solution?
(From the periodic table: 1 mol K = 39.10 g; 1 mol Cl = 35.453 g)
Enter the value rounded to three decimal places with no units
Will give BRAINLEST
Answer:
0.012 M
Explanation:
Step 1: Given and required data
Mass of KCl (m): 0.64 gVolume of water (V): 725 mL (We will assume it is equal to the volume of the solution)Molar mass of KCl (M): 74.553 g/molStep 2: Calculate the moles (n) of solute (KCl)
We will use the following expression.
n = m/M = 0.64 g / (74.553 g/mol) = 8.6 × 10⁻³ mol
Step 3: Calculate the molar concentration (C) of the solution
The molarity is equal to the moles of solute divided by the liters of solution.
C = 8.6 × 10⁻³ mol/0.725 L = 0.012 M
How can we solve food insecurity while reducing food waste?
o inventory food supplies to avoid overbuying
O donate unused food to food banks
O purchase only as much food as you need
O don't throw scraps in the landfill
Answer:
donate unused food to food banks
Explanation:
Becuse food banks processes food to make very fine particles which is mixed with soil and can be given to the plants
1
What is the name of Ba3(PO4)2?
O a. Tribarium Diphosphate
tof
O b. Triboron Diphosphate
O c. Boron Phosphate
O d. Barium Phosphate
Answer:
The answer is barium phosphate
The following molecular equation represents the reaction that occurs when aqueous solutions of silver(I) nitrate and iron(III) chloride are combined
3AgNO3(aq) + FeCl3(aq) → 3AgCl(s) + Fe(NO3), (aq)
Write the balanced net ionic equation for the reaction.
Answer: [tex]3Ag^+(aq)+3Cl^-(aq)\rightarrow 3AgCl(s)[/tex]
Explanation:
Complete ionic equation : In complete ionic equation, all the substance that are strong electrolytes and are represented in the form of ions.
The complete ionic equation will be:
[tex]3Ag^+(aq)+3NO_3^-(aq)+Fe^{3+}(aq)+3Cl^-(aq)\rightarrow 3AgCl(s)+Fe^{3+}(aq)+3NO_3^-(aq)[/tex]
Net ionic equation : In the net ionic equations, we do not not include the spectator ions in the equations.
Spectator ions : The ions present on reactant and product side which do not participate in a reactions. The same ions present on both the sides.
In this equation, [tex]Fe^{3+}[/tex] and [tex]NO_3^-[/tex] are the spectator ions.
By removing the spectator ions from the balanced ionic equation, we get the net ionic equation.
The net ionic equation will be:
[tex]3Ag^+(aq)+3Cl^-(aq)\rightarrow 3AgCl(s)[/tex]
If the mercury in a manometer raises 30.0 millimeters due to a change in pressure, what is the corresponding change in pressure in atm?
Answer:
0.03947 atm
Explanation:
The relationship between mmHg and atm is given as;
1 atm = 760 mmHg
x atm = 30 mmHg
Upon solving for x;
x * 760 = 30 * 1
x = 30 / 760 = 0.03947 atm
Does ionic or covalent form solid crystals?
Answer:
I hope it help
your welcome
Fred is about to order a stack of four pancakes with butter and syrup, but he wonders how much he would need to exercise to burn off the Calories from it. He pulls out his cell phone and finds the nutritional information for the stack of pancakes. He notes that a serving has 181g of carbohydrates, 27g of fat, and 16g of protein. Now, he has to convert these values into Calories.
Running at a pace of 8 minutes per mile burns 14 Calories/minute. How many minutes would he have to run at an 8 minutes per mile pace to bum off the Calories from the stack of pancakes?
Answer:
The correct answer is - 73.64 minutes.
Explanation:
We know that each gram of protein and carbohydrate produces 4 calories of energy whereas fat produces 9 cal energy per gram.
So, the Calories from carbohydrates
= 181 ×4
= 724 Cal
and, 27 g fat produces = 27 × 9 = 243 Cal
and, 16 g protien = 16 × 4 = 64 Cal
so the total energy will be - 243+ 724+ 64 = 1031 Cal
Thus, the time Fred need to run = 1031/14 =73.64 min
Calculate the volume of concentrated HCl (12 M) needed to convert the sodium benzoate back to benzoic acid.
The question is incomplete, the complete question is;
Calculate the volume of concentrated HCL (12 M) needed to convert 1.5 g of sodium benzoate back to benzoic acid.
Answer:
8.33 * 10^-4 L
Explanation:
Equation of the reaction;
C6H5COONa + HCl -------->>>> C6H5COOH + NaCl
Number of moles of sodium benzoate = mass/molar mass
molar mass of sodium benzoate =144.11 g/mol
mass of sodium benzoate = 1.5 g
Number of moles of sodium benzoate = 1.5g/144.11 g/mol
Number of moles of sodium benzoate = 0.01 moles
Since the reaction is 1:1, 0.01 moles of HCl reacted.
but;
n = CV
n = number of moles
C = concentration
V = volume
V = n/C
V = 0.01 moles/12 M
V = 8.33 * 10^-4 L
The fertilization in __________happens outside the female's body
Answer:
Frogs
Explanation:
Answer:
Hello there! I'm assuming frog and or dog :)
Stoichiometric relationship
1. How many moles of oxygen will be produced from the decomposition of 3 moles of KCIO3?
Balanced Equation: 2 KCIO3 ⇒ 2 KCl + 3 O2
3 mol KClO3 x [tex]\frac{3 mol O2}{2 mol KClO3}[/tex] = 4.5 mol O2
PLS HELP ME WITH THIS ILL GIVE BRAINLIEST
Answer:
1 qualiative physical
2 qualiative chemical
3 quantitative physcial
4 quantiative chemical
5qualiative physcial
6quatiative chemcial
7quanatiative physcial
8 qualiative chemical
9quatliate physcial
cuantas moléculas de aspartame están presente en 10.00 gramos de aspartame
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 1.98×10²²molecules of aspartame are present in 10.00 grams of aspartame.
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.
Mathematically,
mole =given mass ÷ molar mass
=10.00 ÷ 294.30
=0.033moles
number of molecules= Avogadro's number × number of moles
=6.022×10²³× 0.033
= 1.98×10²²molecules
Therefore, 1.98×10²²molecules of aspartame are present in 10.00 grams of aspartame.
To know more about mole, here:
https://brainly.com/question/15209553
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Krypton occupies 10.8 L at a pressure of 0.38 atm. Find the volume, in liters, of the krypton when the pressure is increased to 1.6 atm at the same temperature.
Answer:
New volume V2 = 2.565 L
Explanation:
Given:
Old volume V1 = 10.8 L
Old pressure P1 = 0.38 atm
New presuure P2 = 1.6 atm
Find:
New volume V2
Computation:
P1V1 = P2V2
So,
10.8 x 0.38 = V2 x 1.6
New volume V2 = 2.565 L
I need help answering that middle question
Answer: 153
Explanation:
californium is a synthetic radioactive element found on the bottom row of the periodic table, along with other actinides.
It was first discovered in 1950 at the University of California Radiation Laboratory in Berkeley by bombarding curium with alpha particles (helium nuclei). Pure californium metal has a silvery-white appearance and is soft enough to be easily cut with razor blade.
In initial experiments with californium in its concentrated form began in 1958.
Since then, 20 isotopes of californium have been characterize, with mass numbers ranging from 237 to 256. One of these isotopes is californium-252, which was first isolated from a neutron-irradiated sample of plutonium-239. As an exclusively synthetically made element (it cannot be found in nature),
californium-252 is very rare an is produced via neutron bombardment in high flux isotope reactor or particle accelerators.
On this,page we walk through some of the properties and uses of his unique isotope and provide additional resources for your reference.
Hope this helps! :)
In a technique used for surface analysis called auger electron spectroscopy (AES), electrons are accelerated toward a metal surface. These electrons cause the emissions of secondary electrons (called auger electrons) from the metal surface. The kinetic energy of the auger electrons depends on the composition of the surface. The presence of oxygen atoms on the surface results in auger electrons with a kinetic energy of approximately 520 eV .
Required:
What is the de Broglie wavelength of one of these electrons?
Answer:
the de Broglie wavelength of one of the electrons is 5.3787 × 10⁻¹¹ m
Explanation:
Given the data in the question;
we know that; ( electron volt ) 1 eV = 1.602 × 10⁻¹⁹ J
so given that Kinetic Energy KE = 520 eV
KE = 520 × 1.602 × 10⁻¹⁹ = 8.3304 × 10⁻¹⁷ J
we know that;
Kinetic Energy = 1/2 × mv²
where m is the electron mass
and mass of electron is 9.109 × 10⁻³¹ kilograms
so
8.3304 × 10⁻¹⁷ = 1/2 × 9.109 × 10⁻¹⁷× v²
v = √[(8.3304 × 10⁻¹⁷) / (1/2 × 9.109 × 10⁻³¹)]
v = 1.3524 × 10⁷ m/s
speed of the electron v = 1.3524 × 10⁷ m/s
now, de Broglie equation;
wavelength λ = h / mv
where h is Planck constant ( 6.626 × 10⁻³⁴ m² kg / s )
so we substitute
wavelength λ = 6.626 × 10⁻³⁴ / ( 9.109 × 10⁻³¹ × 1.3524 × 10⁷)
wavelength λ = 5.3787 × 10⁻¹¹ m
Therefore, the de Broglie wavelength of one of the electrons is 5.3787 × 10⁻¹¹ m
A student added several drops of a clear liquid to an unknown liquid in each of four test tubes. The results are shown above. These are all examples of a chemical reaction.
true or false
explain why the definition of philosophy as the love of wisdom in insufficient?
Answer:
The word “philosophy” literally means the “love” (philo in Greek) of “wisdom” (sophia). So, a philosopher is somebody who loves wisdom. This, of course, leaves us with 2 important questions: What is wisdom? And what does it mean to love wisdom?
The idea of philosophy goes all the way back to ancient Greece. It is said that the philosopher Pythagoras in the 6th century BCE was the 1st to call himself a philosopher—a philosophos, or “lover of wisdom.” In calling himself this, he was not claiming to be wise. Instead, he was merely saying that he was somebody who valued or cherished wisdom.
Later, the philosopher Plato, who lived in the 5th century BCE, explored these ideas in more depth. In a text called the Symposium, Plato claimed that a philosopher was somebody who was “between the wise and the ignorant.” In other words, a philosopher cared about wisdom but also knew that they were ignorant (we will see tomorrow how Plato was influenced in this by his teacher, Socrates).
Explanation:
How much water needs to be added to 100 mL of a 20%w solution of copper (II) sulfate to prepare a 0.01-M solution?
Answer:
12430mL of water must be added
Explanation:
To solve this question we need to convert the 20%w of CuSO₄ to molarity. Then, using the diulution factor we can find the amount of water required:
20g CuSO₄ / 100mL * (1mol / 159.609g CuSO₄) = 0.1253 moles / 100mL = 0.1253mol / 0.1L =
1.25M is the concentration of CuSO₄. To dilute this concentration to 0.01M, the dilution factor must be of:
1.25M / 0.01M = 125 times must be diluted the solution.
As the volume of the concentrated solution is 100mL, the total volume of the solution to have a 0.01M solution must be of:
100mL * 125 times = 12530mL is the final volume of the solution. That means the amount of water added must be of:
12530mL - 100mL =
12430mL of water must be addedHow has the United States government tried to preserve water sources?
Answer:
Implement rainwater harvesting systems to collect and store rainwater for drinking or recharging underground aquifers. Build wells to extract groundwater from underground aquifers. Provide home water-treatment capability through the use of filters, solar disinfection, or flocculants, to make drinking water safe.
Explanation:
the government of the United States preserves water sources by making waste water treatment and preventing water pollution
When salt water is heated leaving behind solid salt, this is separating a mixture by what method?
A)
chromatography
B)
evaporation
Eliminate
filtration
D)
sifting
Answer:
option B is correct answer of this question
it is. Evaporation
Answer:
It's filtration!
Explanation:
Filtration is a physical chemical operation that separates solid matter and fluid from a mixture!