Answer:
The d-block elements are all metals and most have one or more chemically active d-orbital electrons. Because there is a relatively small difference in the energy of the different d-orbital electrons, the number of electrons participating in chemical bonding can vary.
Answer:
the d block element are all metals and most have one ore more chemically active d-orbital electrons.because there is a realatively small differernce in the energy of the different d-orbital electrons ,the number ofelectrons participating in chemical bonding can vary.Which of the following is correct?
a. One molecule of methane reacts with two molecules of oxygen to produce one molecule of carbon dioxide and two molecules of water.
b. One gram of methane reacts with two grams of oxygen to produce one gram of carbon dioxide and two grams of water.
c. One mole of methane reacts with two moles of oxygen to produce one mole of carbon dioxide and 2 moles of water.
d. a and c are correct.
Answer:
The correct option is d. a and c are correct.
Explanation:
First, we will write a balanced equation for the reaction between methane (CH₄) and oxygen (O₂).
The reaction between methane (CH₄) and oxygen (O₂) gives carbon dioxide (CO₂) and water (H₂O). The balanced equation for the reaction is shown below
CH₄ + 2O₂ → CO₂ + 2H₂O
The number beside each molecule on the reactant side indicates the number of the individual molecules required for complete reaction and also the number beside each molecule on the product side indicates the number of the individual molecules produces in the reaction.
This means,
One molecule of methane will react with two molecules of oxygen to produce one molecule of carbon dioxide and two molecules of water. Hence, option a is correct.
From,
Number of molecules = Number of moles × Avogadro's number
Since Avogadro's number is constant, hence, the equation also means,
One mole of methane will react with two moles of oxygen to produce one mole of carbon dioxide and two moles of water. Hence, option c is correct.
For the mass relationship,
Mass = Number of moles × Molar mass
Molar mass of methane = 12 + 1(4) = 16 g/mol;
∴1g of methane = 0.0625 mole
Molar mass of oxygen = 16 g/mol;
∴2g of oxygen = 0.125 mole
Molar mass of carbon dioxide = 12 + 16(2) = 44 g/mol;
∴1g of CO₂ = 0.02272 mole
Molar mass of water = 1(2) + 16 = 18 g/mol;
∴2g of water = 0.11111 mole
From the equation 0.0625 mole of methane reacts with 0.125 mole of oxygen to produce 0.0625 mole of carbon dioxide and 0.125 moles of water.
Hence, option b is not correct.
SOLVE Use the density formula to solve the following problems. A sample of a substance has a volume of 60.5 mL and a density of 1.20 g/mL. What is the mass of the sample?
The mass of the sample is 72.6 g. when a sample has a volume of 60.5 mL and a density of 1.20 g/mL.
What is the density?Density may be defined as the physical property of any object. It may be characterized as the measurement of quantity or mass per unit of volume in a particular substance.
According to the question, the volume of a sample = 60.5 mL.
The density of a sample = 1.20 g/mL.
Now, the formula for density is as follows:
Density = Mass/Volume.
But we have to calculate the mass of the sample, so the modified formula is = Mass = Density x Volume.
∴ Mass = 1.20 g/mL x 60.5 mL = 72.6 g.
Therefore, the mass of the sample is 72.6 g. when a sample has a volume of 60.5 mL and a density of 1.20 g/mL.
To learn more about Density, refer to the link:
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what labatory activity involves a chemical change
Answer:
buring of paper, burning of wood etc are the examples of chemical change
WORTH 60 POINTS DONT PLAGIARIZE OR WILL REPORT. thanks :) You and your family are going on a trip in Europe. Calculate the speed in the following picture. Show your work and include units. Include 4-5 sentences explaining.
Answer:80
Explanation:
It would be 80 kilometers an hour. All you have to do is divide the total distance traveled which in this case is 240 kilometers, by the number of hours driven which is 3 hours.
which best describes an element? - a pure substance - a type of a mixture - a pure compound - an impure substance
Answer:
A pure substance
Explanation:
An element is a pure substance.
It is only made up of atoms of the same type.
What is the weight of 2.5 ml of a solution that has a density of 1 g/mL?
Answer:
Density=mass / volume.
1= mass × 2.5.
mass = 2.5×1.
mass=2.5g
How many centimeters are in 5.46 meters
Answer: 546 meters
Explanation: multiply the length value by 100
Suppose you are asked to determine whether a nugget is made of gold on the basis of its density. You weigh the nugget and find that it has a mass of 163 grams (g). Then you carefully add it to a graduated cylinder that contains 50.0 milliliters (mL) of water and observe that the water level in the cylinder rises to 58.5 mL. What is the density of the nugget in grams per cubic centimeter?
Answer:
Explanation:
density is mass over volume
Mass = 163 grams
Volume = 58.5 - 50.0 = 8.5
density = 163 / 8.5
density = 19.176
To 3 figures that 19.2 grams / mL
Answer:
density is mass over volume
Mass = 163 grams
Volume = 58.5 - 50.0 = 8.5
density = 163 / 8.5
density = 19.176
To 3 figures that 19.2 grams / mL
Explanation:
Which of the following describes the difference between Carbon−12 and Carbon−14? A. Carbon-12 has 12 electrons, 12 protons, and 12 neutrons; Carbon−14 has 14 electrons, 14 protons, and 14 neutrons. Both are radioactive isotopes. B. Carbon-12 has 6 electrons, 6 protons, and 6 neutrons; Carbon−14 has 6 electrons, 6 protons, and 8 neutrons. Both are radioactive isotopes. C. Carbon−12 has 6 electrons, 6 protons, and 6 neutrons; Carbon−14 has 6 electrons, 6 protons, and 8 neutrons. Only Carbon−14 is a radioactive isotope. D. Carbon−12 has 6 electrons, 6 protons, and 6 neutrons; Carbon−14 has 6 electrons, 6 protons, and 8 neutrons. They are not radioactive isotopes.
Answer:
B
Explanation:
Why can't an atom lose or gain a proton?
Are Elements on the Period Table of Elements?
Yes or No?
Answer:
Yes they are I guess so
:)
Answer:
Yes it is
Hope it helps
Tessa knows that the sea grape tree can grow well in areas of high st and poor soil. She has seen sea grape growing along the beach strands and coastal hammocks of south Florida. She sets up an experiment to see which amount of salt is best for sea grape. She chooses two plants. She gives pure water to the first plant and a strong salt water solution could Tessa do to improve her experiment? the econd. Then, she measures growth.
Entrance Question: What is a physical trait? Explain using complete sentences.
Answer: A physical trait is a defining aspect or feature of your body or other subject that you can see visually.
Explanation:
You have a stock solution that is 226mg/mL and you need 10mL of a working solution that is 15mg/mL. What is the volume of stock solution will you need to dilute to have 10mL of working solution at the above concentration. State your answer to two decimals.
Answer: 0.67 ml
Explanation:
According to the dilution law,
[tex]C_1V_1=C_2V_2[/tex]
where,
[tex]C_1[/tex] = concentration of stock solution = 226 mg/ml
[tex]V_1[/tex] = volume of stock solution = ?
[tex]C_2[/tex] = concentration of working solution= 15 mg/ml
[tex]V_2[/tex] = volume of working solution= 10 ml
Putting in the values we get:
[tex]226mg/ml\times V_1ml=15mg/ml\times 10ml[/tex]
[tex]V_1=0.67ml[/tex]
Thus volume of stock solution needed to dilute to have 10mL of working solution at the above concentration is 0.67 ml
1) A person counts the number of flowers she sees on different types of plants. She records data
every week.
a. Independent Variable (IV):
b. Dependent Variable (DV):
c. Control Group:
d. Constants:
Answer:
Explanation:
An independent variable is the variable that is intentionally altered or changed during the course of an experiment and is not dependent on another variable. The independent variable from the narration in the question is the different types of plants (as seen, the type of plant was intentionally changed during the course of the experiment).
A dependent variable is the variable whose "outcome" is assumed/expected to be dependent on another variable called the independent variable. The dependent variable from the narration in the question is the number of flowers (as seen, the outcome/number of flowers is expected to be dependent on the type of plant).
The control group is the group that is used as a reference (or benchmark) for the sake of comparisons while reporting an experiment. From the narration in the question, nothing was mentioned as regards the control group.
Constants are unchanged factors that are maintained throughout the course of an experiment. From the narration, the constant is the time in which her observations are done which is weekly (every week).
INDEPENDENT VARIABLE:
Independent variable is the variable that is changed or manipulated in an experiment in order to bring about a response.DEPENDENT VARIABLE:
Dependent variable is the variable that is measured or recorded in an experiment.CONTROL VARIABLE:
Control variable or constant is the variable that is kept unchanged throughout the experiment. According to this question, a person conducts an experiment by counting the number of flowers she sees on different types of plants. She records data every week.In this experiment;
Independent Variable (IV) is the different types of plants because it was changed. Dependent Variable (DV) is the number of flowers because it is recorded. Control Group: NoneConstants: Duration/time of recordingLearn more about IV, DV and constant at: https://brainly.com/question/17498238?referrer=searchResults
Express 0.044 km in meters.
Answer:
44
Explanation:
You multiply the length value by 1000
Answer:
0.044 km × 1000 = 44 meters
Which statement best describes the chart? Heat was removed from the activation energy to create the product. Heat was added to create the product. The products have less energy than the reactants. The products have the same energy as the reactants.
Answer:
A. Heat … Get the answers you need, now! ... A. Heat was removed from the activation energy to create the product. ... C. The products have less energy than the reactants. D. The products have the same energy as the reactants.
Explanation:
Answer:
its B. Heat was added to create the product.
Explanation:
just took the test on edg2020 :)
I need help will give you fives star
Answer:
2
Explanation:
The maximum amount of electrons in an atom that can share those quantum numbers because of the spin quantum numbers (ms) +1/2 and -1/2.
what is the answer of (9*10^4)^3?
Answer:
7.29 x 10^14
Hope this helped! :)
How many cubic centimeters of an ore containing only 0.22% gold (by mass) must be processed to obtain $100.00 worth of gold? The density of the ore is 8.0 g/cm3 and the price of gold is $818 per troy ounce. (14.6 troy oz = 1.0 ordinary pound, called an avoirdupois pound; 1 lb = 454 g)
Answer:
The cubic centimetres of the ore containing 0.22% gold (by mass) that must be processed to obtain the $100.00 worth of gold is approximately 216 cm³
Explanation:
The percentage by mass of gold in the ore = 0.22%
The density of the ore = 8.0 g/cm³
The price of the gold = $818 per troy ounce
14.6 troy oz = 1.0 pound
1 lb = 454 g
Given that one troy ounce = $818
$100 worth of gold = 1/818 ×100 troy ounce = 100/818 troy ounce
1 troy oz = 1.0/14.6 lb
100/818 troy oz = 100/818 × 1.0/14.6 lb = 250/29857 lb ≈ 0.0084 lb
1 lb = 454 g
250/29857 lb = 454 × 250/29857 g ≈ 3.8015 g
$100 = 3.8015 g worth of gold
The mass, M, of the ore containing 3.8015 g of gold is given as follows;
0.22% of M = 3.8015 g
0.22/100 × M = 3.8015 g
M = 3.8015 g × 100/0.22 = 1727.933 g
The volume, V, of the ore containing 3.8015 g of gold is given as follows;
Density of ore = Mass of ore/(Volume of ore)
Volume of ore = Mass of ore /(Density of ore)
The density of the ore = 8.0 g/cm³
Volume of ore = 1727.933 g /(8.0 g/cm³) = 215.99 cm³ ≈ 216 cm³
Therefore, the cubic centimetres of the ore containing 0.22% gold (by mass) that must be processed to obtain the $100.00 worth of gold ≈ 216 cm³.
Carlos has 1.2 m a long piece of wood? how long is this in millimeters
Answer:
1200 millimeters
Explanation:
if there are 1000 millimeters in a meter then you have to multiply 1.2 meters by 1000 to get the number of millimeters. 1.2*1000=1200mm
One half of a balanced chemical equation is shown. 3Mg(OH)2 + 2H3PO4
Answer:
3Mg(OH)2 + 2H3PO4 = Mg3(PO4)2 + 2H3O
Explanation:
Question:
Which lists the numbers of each atom the other half of the equation would contain?
Equation:
3Mg(OH)2 + 2H3PO4
Options:
3 Mg, 2 P, 14 O, 12 H Mg, 2 P, 14 O, 6 H 3 Mg, 8 P, 7 O, 6 H 6 Mg, 6 P, 2 O, 12 HAnswer:
A) 3 Mg, 2 P, 14 O, 12 H
Explanation:
I just did the test on edge 2020 and got the answer right. Also, my dog said hi.
5 Laboratory instructions require students to as- semble a measuring device containing many small parts and springs. Which piece of safety equipment would be required in this investigation
A apron
B gloves
c lab coat
D safety glasses
Answer
C lab coat
Explanation
Answer:
c
Explanation:
Which of the following is an example of chemical energy changing into radiant energy?
A. A fireplace glowing when lighted B. A plant using sunlight to make food C. A child on a swing slowing down as she swings upwards D. A coil of a toaster glowing when the toaster is switched on
Answer:
D. A coil of a toaster glowing when the toaster is switched on
Explanation:
Hydrocarbons that contoins least double bond are
Answer:
Chemistry has taught that ;
Unsaturated hydrocarbon molecules that contain one or more double bonds are called alkenes.
Alkynes are unsaturated hydrocarbons due to the fact that some of the carbons are connected to fewer than four neighbouring atoms.
Note : Alkenes contain at least one double bond, while alkynes contain at least one triple bond.
Explanation:
A chemist encounters an unknown metal. They drop the metal into a graduated cylinder containing water, and find the volume change is 6.9 mL. If the metal weighs 4.9 g, what is the density of the metal?
Answer:
The density of the metal is 0.561 g/mL
Explanation:
The computation of the density of the metal is shown below;
As we know that
The Density of the metal is
[tex]= \frac{mass}{volume}[/tex]
where,
Mass = 4.9g
Change in volume = 6.9 mL
Now place these values to the above formula
So, the density of the metal is
[tex]= \frac{4.9g}{6.9mL}[/tex]
= 0.561 g/mL
Hence, the density of the metal is 0.561 g/mL
We simply applied the above formula so that the correct density could arrive
How do scientists calculate the energy and frequency of photons?
three examples of disaccharides
Answer:
sucrose
lactose
maltose
Hope this helps :)
I would really appreciate help on this! Thank you.
Classify the following as a chemical or
physical property:
Chlorofluorocarbons destroy ozone.
Answer: Chemical
Explanation:
The reaction of destroying is a chemical change in the ozone molecules.
13.26 g has
significant figures
1.
0
1
2
3
4.
Answer:
13.26 g has 4 significant figures