Answer: Physical change
Explanation: I said physical change because its changing the form of the substance and also solid to gas are sublimating
What do these two changes have in common? snails growing shells a slice of banana turning brown
Answer:
both are done due to the enviroment??
In the following reaction, the partial
pressure at equilibrium for each of the
products, CO and water vapor at 990°
C, is 11.0 atm and the partial pressure
for each of the reactants, H2 and CO2,
at equilibrium is 8.70 atm. What is Kp?
H2(g) + CO2(g) + H2O(g) + CO(g)
Kp = [?]
Answer:
H2+CO2=H2O+CO
Kp=(pCO)(pH2O)/(pH2)(pCO2)
= 11×11/8.70×8.70
=1.60
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 %
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:
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.
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:
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.
A system gains 652 kJ of heat, resulting in a change in internal energy of the system equal to +241 kJ. How much work is done?
Answer:
-411 kj
Explanation:
We solve by using this formula
∆U = ∆Q + ∆W
This formula is the first law of thermodynamics
Change in internal energy U = +241
Heat gained by system Q = 652
Putting the value into the equation
+241 = 652 + W
Workdone = 241 - 652
Workdone = -411 kj
Since work done is negative it means that work was done by the system
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 mixtureWrite an essay about the harm ful effects of sunlight to people. Minimum of ten sentences cite some expale of possible
Answer: See explanation
Explanation:
The sun is a star that's made up of several gases. It is known to be the most vital source of energy to living things.
Despite the importance of the sun in our lives, it's still harmful when one is exposed to it. They rays of light that's given our by the sun can be harmful to us.
Being exposed to the sun can cause sunburn and this can result in the damage of skin cells and development of cancer. Also, sunlight can lead to early aging as the skin ages faster when one is exposed to the sun.
Furthermore, exposure to sunlight can lead to eye injuries the tissue in our eyes can be damaged by the UV rays. Lastly, it also brings about lowered immune system.
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
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
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.
Thallium-201 has a half-life 73 hours. If 4.0 mg of thallium-201 disintegrates over a period of 6.0 days and 2 hours, how many milligrams of thallium-201 will remain?
Answer:
[tex]\huge\boxed{\sf 1.0 \ mg}[/tex]
Explanation:
Half-life = 73 hours
Disintegration period = 6 days 2 hours = (6*24) hours + 2 hours
= 144 hours + 2 hours
= 146 hours
No. of Half lives = Disintegration period / Half-lifeNo. of Half lives = 146 hours / 73 hours
No. of Half lives = 2
Hence, there are 2 half lives passed in 6 days 2 hours.
Amount of thallium-201 left after first half-life:
= 4.0 mg / 2
= 2.0 mg
Amount of thallium-201 left after second half-life:
= 2.0 mg / 2
= 1.0 mg
Hence, the amount of thallium-201 left after 6.0 days and 2 hours is 1.0 mg.
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807Do noble gases form bonds? Why or why not?
◕‿↼ Hey There!
Answer → Source Noble Gases have a full valence shell, which is why they rarely form bonds with other atoms.
✨ Hope This Helps!✨
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.
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 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.
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.
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
Sometimes the number of electrons in an atom changes. These atoms are called what
Answer:
ions
Explanation:
What is the pH of a 1.0 x 10-2 M HNO3 solution?
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 :)
What are the two most recent fossils that have been found in New york?
cie
Explanation:cioserra s ojs queengo o m me vengoe volo
If there are 27 grams of nitrogen dioxide at STP how many liters does this occupy?
Answer:
30 liters
Explanation:
For the following equation insert the correct coefficients that would balance the equation. If no coefficient is need please insert the NUMBER 1.
1. CH4 + O2 --> CO2 + H2O
Answer:
1CH₄ + 2O₂ -> 1CO₂ + 2H₂O
Explanation:
Reactants:
1 C
4 H
4 O
Products:
1 C
4 H
4 O
The equation is balanced.
What is the oxidation state of copper in Cu(C2H3O2)2? +2 -1 -2 +4 +1
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.
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.
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
