Answer:
1. 7 (a neutral solution)
Answer: 10-7= 0.0000001 moles per liter
2. 5.6 (unpolluted rainwater)
Answer: 10-5.6 = 0.0000025 moles per liter
3. 3.7 (first acid rain sample in North America)
Answer: 10-3.7 = 0.00020 moles per liter
The concentration of H+ in the Hubbard Brook sample is 0.00020/0.0000025, which is 80 times higher than the H+ concentration in unpolluted rainwater.
Explanation:
how are the functions of a flower's stamen and pistil related to reproduction?
Answer: the essential parts of a flower
Explanation:
are engaged with seed creation. In the event that a blossom contains both useful stamens and pistils, it is known as an ideal bloom, regardless of whether it doesn't contain petals and sepals. On the off chance that either stamens or pistils are deficient with regards to, the blossom is called imperfect.
What is so important about DNA? Select all correct answers.
A. DNA is found in all organisms and carries instructions to build those organisms
B. DNA found in one organism probably shares similar instructions found in another species
C. DNA is composed of only four bases that repeat in a sequence that is different for each
species
D. Some organisms don't actually have DNA
E. The DNA of each organism is made out of different types of chemicals
Answer:
A and C
Explanation:
DNA is what makes up you and me and DNA is composed of four bases adenine, guanine, thymine, and cytosine. The others are not true.
If there are 27 grams of nitrogen dioxide at STP how many liters does this occupy?
Answer:
30 liters
Explanation:
What is the difference between soil and sand
Explanation:
The terms ‘sand’ and ‘soil’ are often interchanged and used synonymously with one another. Many people consider them the same, but when scrutinized, they are quite different from each other. First and foremost, sand is a type of soil–so is silt, clay, peat, and loam. These types of soils are generated when rocks break up into their constituent parts and are acted upon by outside forces, such as wind, water, and natural salts. The broad definition of soil refers to the loose layer of earth that covers the surface of the planet. Sand, on the other hand, is defined as loose material that consists of rocks or mineral grains.
Answer:
soil is defined as the top layer of the land surface of the earth that is composed of disintegrated rock particles, humus, water, and air.
sand is defined as a loose material that consists of rocks or mineral grains.
Explanation:
how to obtain pure aluminium oxide from sodium aluminate. pls help.
Answer:
By Bayer process.
Explanation:
In the Bayer process, bauxite ore is heated in a pressure vessel along with a sodium hydroxide solution (caustic soda) at a temperature of 150 to 200 °C. At these temperatures, the aluminium is dissolved as sodium aluminate (primarily [Al(OH)4]−) in an extraction process.
A solution of 12M HCl is diluted so that it goes from 550mL to a total volume of 1000mL. What is the new concentration of the solution?
Answer:
6.6M
Explanation:
C=concentration
V=Volume
C1V1=C2V2
rearrange formula to find C2
(C1V1)/V2= C2
(12M x 550mL)/1000mL= C2
6600M*mL*/1000*mL* =C2 (cancel units)
6.6M=C2
What happens as you decrease the temperature of a solution?
A.
The number of solute particles increases.
B.
The number of solute particles decreases.
C.
The rate of dissolution increases.
D.
The rate of dissolution decreases.
E.
The temperature has no effect on the rate of dissolution.
Answer:
D is the answer
Explanation:
On a certain hot day the atmospheric pressure was 1 atm and the temperature was 37°C. On this day 1 L sample of atmospheric gases was collected and analyzed. It was found to contain among other gases 9.38 x 10-3 mol of O2 gas, 2.46 x 10-8 mol of H2 gas and 1.79 x 10-4 mol of water vapor. If you put these amounts of the three gases in a sealed 1L tank at 1 atm and 37°C, will the combustion of hydrogen gas be spontaneous at these conditions?
Answer:
Yes, the combustion of hydrogen is spontaneous from the given conditions.
Explanation:
Let look at the reaction:
[tex]2H_2_{(g)} + O_2_{(g)} \to 2H_2O_{(g)}[/tex]
[tex]K_p = \dfrac{[P(H_2O)]^2}{[P(H_2)^2\times P(O_2)]} ----- (1)[/tex]
The total pressure of the tank = 1 atm
[tex]\mathtt{Pressure \ of \ the \ gas = moles \ fraction \of \ gas \times total \ pressure}[/tex]
Thus, pressure of [tex]O_2[/tex] gas = [tex]\dfrac{9.38 \times 10^{-3} }{(9.38 \times 10^{-3} + 2.46 \times 10^{-8} + 1.79 \times 10^{-4}} \times 1 atm[/tex]
[tex]P(O_2) = 0.9813 atm[/tex]
Pressure of [tex]H_2O[/tex] gas =[tex]\dfrac{1.78 \times 10^{-4}}{9.38 \times 10^{-3} + 2.46 \times 1)^{-8} + 1.78 \times 10^{-4}} \times 1 \ atm[/tex]
Pressure of H_2 gas = [tex]2.573 \times 10^{-6} \ atm[/tex]
From equation (1);
[tex]K_p = \dfrac{(0.0187)^2}{(2.573 \times 10^{-6})^2 \times (0.913) } \\ \\ K_p = 5.383 \times 10^7[/tex]
So, applying the equation:
[tex]\Delta G^0 = -RT In K_p \\ \\ = -8.314 \times (300)K \times IN(5.383 \times 10^7) \\ \\ = -45880.109 J \\ \\ = -45.800 \ kJ\\ \\[/tex]
Thus;
[tex]\Delta G^0 < 0[/tex]
Thus, Yes the combustion of hydrogen is spontaneous from the above conditions. From thermodynamics, we realize that assuming ∆G is negative, the reaction is spontaneous. Again we understand that ∆G=∆H-T∆S. However, for combustion, water will definitely be formed.
Finally, we can conclude that;
∆H is negative;
∆S is positive; &
∆G is also negative.
Thus, from above, we conclude combustion of hydrogen is spontaneous.
The combustion of hydrogen gas with the oxygen gas for the formation of the water vapor is a spontaneous reaction.
How do we know reaction is spontaneous?To know about the condition that the given reaction is spontaneous or not we will use the below equation and must get the negative value:
ΔG° = -RTlnKp, where
R = universal gas constant
T = temperature
Kp = partial pressure constant
Firstly we have to calculate the value of Kp.
Given chemical reaction is:
2H₂(g) + O₂(g) → 2H₂O(g)
Value of Kp for the given reaction is:
Kp = [p(H₂O)]² / [p(H₂)]².[p(O₂)]
Partial pressure will be calculated as:
p = mole fraction × total pressure
Given that total pressure of gas = 1atm
p(H₂O) = (1.79×10⁻⁴ / 1.79×10⁻⁴+2.46×10⁻⁸+9.38×10⁻³) × 1 = 0.0187
p(H₂) = (2.46×10⁻⁸ / 1.79×10⁻⁴+2.46×10⁻⁸+9.38×10⁻³) × 1 = 2.573 × 10⁻⁶
p(O₂) = (9.38×10⁻³ / 1.79×10⁻⁴+2.46×10⁻⁸+9.38×10⁻³) × 1 = 0.913
Putting all these values on the equation of Kp, we get
Kp = (0.0187)² / (2.573 × 10⁻⁶)²(0.913) = 5.383 × 10⁷
Now putting values in the first equation we get,
ΔG° = -(8.314)(300)ln(5.383 × 10⁷)
ΔG° = -45,800 kJ
Hence, given reaction is spontaneous.
To know more about spontaneous reaction, visit the below link:
https://brainly.com/question/24376583
Jess is baking a cake. Part of the recipe has Jess mix butter and water. He notices that the two substances don't mix. He is confused because water and butter are both covalent compounds. Explain why the butter and water are NOT mixing in the bowl.
Answer:
butter and water don't mix because water is polar and butter is nonpolar
Explanation:
for them to be able to mix they would need to be both polar or both nonpolar.
Mass = 22g Volume = 2cm3 What is the Density?
Answer:
11g/cm^3
Explanation:
The density of a substance can be found By
density= Mass/volume
From the question
mass = 22 g
volume = 2 cm³
22/2=11
We have the final answer as
11 g/cm³
Answer:
11g/cm^3
Explanation:
It is because the constant formula density is
Density=Mass/ Volume.
Therefore we have
Density=22g/2cm^3
Which is = 11g/cm^3
Match the different methods used for calculating revenue and profit to the formulas used for calculating them. total revenue average revenue marginal revenue gross profit net profit
Answer:
See explanation below
Explanation:
1) Total Revenue:
Total revenue refers to the total amount of income that is generated when a company sells or offers their service.
It is usually calculated as the product of the product or services sold by the quantity.
It is calculated by ;
TR = Q * P
Where TR = Total Revenue
Q = Quantity
P = Price
2.) Average Revenue:
Average revenue is the revenue gotten by a company per unit of output sold. It is calculated by:
AR = TR / Q
Where AR = Average Revenue
TR = Total Revenue
Q. = Quantity
3.) Marginal Revenue:
This is the net revenue that is generated by selling an additional unit of commodity; which is the change in total revealer unit. It is calculated by:
MR = change in Total Revenue / change in Quantity
Where MR = Marginal Revenue
4.) Gross Profit:
Gross profit is the amount of revenue left after factoring out the cost of production and sales and servicing.
It is calculated by subtracting revenue from the cost of goods sold -
Gross Profit = Revenue - Cost of goods sold
Net Profit:
Net profit is the amount of money a company has left after subtracting all interests, tax expenses and cost.
It is calculated by;
Net Profit = Gross Profit - Expenses
1,670,000,000 in
scientific notation pleaseeee
Answer:
1.67 × 10^9
Explanation:
Most of the world’s energy comes from what three sources?
These energy sources are called ______________fuels and they are _____________________ resources.
Answers:
Most of the world’s energy comes from what three sources?
Oil, coal, and gas.
These energy sources are called fossil fuels and they are non-renewable resources.
Fuel type: oil
How it's formed: from the remains of ancient marine organisms
Its uses: transportation, industrial power, heating and lighting, lubricants, petrochemical industry, and use of by-products
Fule type: coal
How it's formed: when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial
Its uses: electricity generation, metal production, cement production, chemical production, gasification, and other industrial uses
Fuel type: gas
How it's formed: decomposed organic matter mixed with mud, silt, and sand on the seafloor
Its uses: heating & cooling buildings, cooking foods, fueling vehicles, and electricity generation
Which statement correctly describes extreme weather?
O A. Extreme weather events follow normal climate patterns.
o O B. Extreme weather events are random occurrences.
O C. Extreme weather events started with global warming.
O D. Extreme weather events are unpredictable until they strike.
Answer: A
Explanation:
Extreme weather events follow normal climate patterns.
18) What is the following number representing: 10m/s West *
3 points
Force
Acceleration
Mass
Area
Pressure
Velocity
Speed
Impulse
Momentum
Speed
Explanation:
The distance travelled by a body per unit time
What types of elements [metals/nonmetals] are found in each of the compounds?
Not a simple answer please
Explanation:
List of All Elements That Are Nonmetals
Hydrogen (sometimes)
Carbon.
Nitrogen.
Oxygen.
Phosphorus.
Sulfur.
Metals:-
Gold.
Silver.
Iron.
Copper.
Nickel.
Aluminum.
Mercury( Liquid metal)
Titanium.
Fluorine.
There are 4 mg of lead present in 2000 g of a water sample. What is the
concentration of lead in m?
Answer: 130 ppm Pb
Explanation:
We use parts per million to express the concentrations of solutions that contain very, very small amounts, often called trace amounts, of a given solute.
More specifically, a solution's concentration in parts per millions tells you the number of parts of solute present for every
10
6
=
1
,
000
,
000
parts of solution. You can thus say that a
1 ppm
solution will contain exactly
1 g
of solute for every
10
6
g
of solution.
In your case, you know that you have
38
mg Pb
⋅
1 g
10
3
mg
=
3.8
⋅
10
−
2
.
g Pb
in exactly
300.0 g
=
3.000
⋅
10
2
.
g solution
This means that you can use this known composition as a conversion factor to scale up the mass of the solution to
10
6
g
10
6
g solution
⋅
3.8
⋅
10
−
2
.
g Pb
3.000
⋅
10
2
g solution
=
130 g Pb
Since this represents the mass of lead present in exactly
10
6
g
of solution, you can say that the solution has a concentration of
concentration
ppm
=
130 ppm Pb
−−−−−−−−−−−−−−−−−−−−−−−−−−−−
The answer is rounded to two sig figs, the number of sig figs you have for the mass of lead present in the sample.
What do all electrolytes have in common?
They have low melting points.
They are polar molecules.
They have mobile ions in solution.
They are compounds of carbon.
The particles of a substance lose energy and change from
a disordered structure with large distances between the particles to
a loosely ordered state.
Which change of state is described?
Answer:
A Liquid
Explanation:
structure with large distance (gas) than goes to a loosely ordered state (liquid)
I hope this helps
Which substance cannot be separated or broken down into simpler substances by chemical means?
table salt
gold wire
candle wax
water vapor
Answer: Gold Wire
Explanation:
Out of all of these options only gold wire is an element, elements are pure and cannot be broken down by any chemical means
hope it helped, good luck :)
You are given a 1.55 g mixture of calcium nitrate and calcium chloride. You dissolve this mixture in 20 mL of water and add an excess of 0.300 M silver nitrate. You collect and dry the resulting precipitate and determine it has a mass of 0.535 grams. Calculate the percent calcium chloride in the original mixture.
Answer:
13.4 (w/w)% of CaCl₂ in the mixture
Explanation:
All the Cl⁻ that comes from CaCl₂ (Calcium chloride) will be precipitate in presence of AgNO₃ as AgCl.
To solve this problem we must find the moles of AgCl = Moles of Cl⁻. As 2 moles of Cl⁻ are in 1 mole of CaCl₂ we can find the moles of CaCl₂ and its mass in order to find mass percent of calcium chloride in the original mixture.
Moles AgCl - Molar mass: 143.32g/mol -:
0.535g * (1mol / 143.32g) = 3.733x10⁻³ moles AgCl = Moles Cl⁻
Moles CaCl₂:
3.733x10⁻³ moles Cl⁻ * (1mol CaCl₂ / 2mol Cl⁻) = 1.866x10⁻³ moles CaCl₂
Mass CaCl₂ -Molar mass: 110.98g/mol-:
1.866x10⁻³ moles CaCl₂ * (110.98g/mol) = 0.207g of CaCl₂ in the mixture
That means mass percent of CaCl₂ is:
0.207g CaCl₂ / 1.55g * 100 =
13.4 (w/w)% of CaCl₂ in the mixtureWhich statement about elements is true?
All substances are made up of elements.
There are approximately 50 elements.
An element is made up of different types of atoms.
Most elements are nonmetal.

Answer:
first one is right.
there are 117 elements, so 2nd option is wrong.
elements are made up of one type of atoms, so 3rd is also wrong.
most elements are metal. so 3rd is wrong
What would it mean if a forecaster claimed, “There will be east winds of 25 to 30 mph."
Answer: It would mean that there is wind originating from the east and blowing west at 25 - 30 mph
How are a moon and an asteroid different? (2 points)
a
A moon revolves around an asteroid, while an asteroid rotates around its axis.
b
A moon revolves around a planet, while an asteroid revolves around a star.
c
A moon revolves around a star, while an asteroid rotates around its axis.
d
A moon rotates around its axis, while an asteroid revolves around a planet.
Answer:
B
Explanation:
Asteroid - A rock that rvolves arounf the sun / star.
Moon - A natural satillite that revolves around earth/ planet.
Which of the following statements is not true? a. Water is polar. b. Water stabilizes temperature. c. Water is essential for life. d. Water is the most abundant atom in Earth’s atmosphere.
Answer: d. Water is the most abundant atom in Earth’s atmosphere.
Explanation:
Water percentage in the atmosphere is 0.001 percent only as it not the major reservoir or source of water. The water is available in the atmosphere in the form of water vapors. These water vapors when aggregate and their concentration becomes high they fall down as rain on earth so the rain is collected in water reservoirs like oceans, rivers, lakes, ponds, aquifers, and other sources of water, which are the components of hydrosphere on earth. So, hydrosphere is most abundant in water. Moreover, water is not an atom instead it is the molecule formed by the combination of two molecules of hydrogen and one molecule of oxygen.
Sometimes the number of electrons in an atom changes. These atoms are called what
Answer:
ions
Explanation:
Compute the percentage of error to the nearest tenth in the student’s calculation if the actual specific heat value for aluminum is 0.9J:g*C.
Complete Question:
1. A block of aluminum with a mass of 140 g is cooled from 98.4°C to 62.2°C with a release of 4817 J of heat. From these data, calculate the specific heat of aluminum.
a. Compute the percentage of error to the nearest tenth in the student's calculation if the actual specific heat value for aluminum is 0.9 J/g°C
Answer:
Percent error = 55.56 %
Explanation:
Given the following data;
Mass = 140 grams
Initial temperature = 62.2°C
Final temperature = 98.4°C
Quantity of heat = 4817 Joules.
To find the specific heat capacity;
Heat capacity is given by the formula;
[tex] Q = mcdt[/tex]
Where;
Q represents the heat capacity or quantity of heat. m represents the mass of an object. c represents the specific heat capacity of water. dt represents the change in temperature.dt = T2- T1
dt = 98.4 - 62.2
dt = 36.2°C
Making c the subject of formula, we have;
[tex] c = \frac {Q}{mdt} [/tex]
Substituting into the equation, we have;
[tex] c = \frac {4817}{140*36.2} [/tex]
[tex] c = \frac {4817}{5068} [/tex]
Specific heat capacity, = 0.95 J/g°C
b. To find the percentage error;
Given the following data;
Actual specific heat capacity = 0.9 J/g°C
Experimental specific heat capacity = 0.95 J/g°C
Percent error can be defined as a measure of the extent to which an experimental value differs from the theoretical value.
Mathematically, it is given by this expression;
[tex] Percent \; error = \frac {experimental \;value - actual \; value}{ actual \;value} *100[/tex]
Substituting into the formula, we have;
[tex] Percent \; error = \frac {0.95 - 0.9 }{ 0.9} *100[/tex]
[tex] Percent \; error = \frac {0.5}{0.9} *100[/tex]
[tex] Percent \; error = 0.5556 *100[/tex]
Percent error = 55.56 %
how did the idea of what a cell was develop overtime
Answer:
experiments
Explanation:
I am not sure but heres my take
Answer:
It was only after the invention of electron microscope that the idea developed
Pls help!
the chemical that is responsible for stopping reaction is called the ____
Answer:
reactant
Explanation:
I watched a chem video and this is what they called it.
what is a chemical equation
Answer:
"Symbolic representation of a chemical reaction in the form of symbols and formulae"
Answer:
A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and formulas.
Explanation:
Example- Zinc metal reacts with dilute sulphuric acid to form zinc sulphate and hydrogen gas. This equation is written as: Zn+H2SO4→ZnSO4+H2.