Answer:
About 80% of the elements on the periodic table are metals.
Explanation:
what is the formula for lead (ll) sulfate
Answer: PbSO4
Explanation: Search on google
Answer:
PbSO4
Explanation:
6) Which of these elements is a metal?
E) C
D) N
A) O
C) Ne
B) Ca
Answer:
Ca
Explanation:
It is on the left side of the periodic table where metals are located.
Answer:
Ca
Explanation:
“surely you have gotten into a car on a cool day and noticed that the metal buckle on your seatbelt feels significantly colder than other things in your car, such as the steering wheel or the center console. Explain why this is” someone please help
Answer:
The metal buckle conducts heat away from the hand than both the steering wheel and center console.
Explanation:
Good conductors are materials that allow both heat and electricity to flow easily through them. Examples of good conductors are metals.
Poor conductors or insulators are materials which do not allow both heat and electricity to flow easily through them. Examples of insulators are most non-metals, plastics, rubber, wool, wood, etc.
On a cool day a metallic object like the buckle of a car's seatbelt will easily conduct heat away from the hand than other materials inside the car like the seat, the seatbelt, the steering wheel and the centre console as these materials are made from insulators or poor conductors.
Therefore, the metal buckle will feel colder to touch than other things in the car because it conducts heat away from the hand than both the steering wheel and center console.
Which of the following chemical equations depicts a balanced ionic equation?
Answer:
Option C. 2OH¯ + Ca²⁺ —> Ca(OH)2
Explanation:
OH¯ + Ca²⁺ —> Ca(OH)2
The above equation can be balance as follow:
OH¯ + Ca²⁺ —> Ca(OH)2
There are 2 atoms of OH on the right side and 1 atom on the left side. It can be balance by putting 2 in front of OH¯ as shown below:
2OH¯ + Ca²⁺ —> Ca(OH)2
Next, we shall balanced the charge on both side. This can be obtained as follow:
Total charge on the left side = –2 + 2
Total charge on the left side = 0
Total charge on the right side = 0
Thus, the charge on both side are equal. Hence, the balance ionic equation is:
2OH¯ + Ca²⁺ —> Ca(OH)2
Evidence in the fossil record points to major asteroid impacts that have caused mass extinctions in which 50%–96% of life on Earth died out.
Answer:
5
Explanation:
What is the mass in grams of 381 mL of ethylene glycol?
Answer:
38
Explanation:
What my favorite food only question for JungKookLuver and jguzman577! Or if u answer I report you!
Answer: Pizza
Explanation: Pizza
Answer:
Shiver me timbers its pizza
Explanation:
Identify the shape of the molecules that could result from each of the hybrid orbitals given below.
Check all of the boxes that apply.
sp^2-orbitals
O bent
O tetrahedral
O trigonal planar
Explanation:
The 5s,5p and 5d orbitals hybridise to form seven sp3 d3 hybrid orbitals. The molecule is then formed with 7 fluorine atoms. The geometry of this molecule is pentagonal bipyramidal . Five F atoms are in one plane directed at corners of a pentagon (equatorial position), with 72º angle between them.
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Answer:
bent and trigonal planar
Explanation:
Which of these solutions would be considered to have a neutral pH?
Ammonia, pH = 9.0
Pure water, pH = 7.0
Coffee, pH = 5.0
Rainwater, pH = 6.0
Answer:
Pure Water.
Explanation:
Solutions with a pH of 1-6 are considered acidic. Solutions with a pH of 8-14 are considered basic. Solutions with a pH of 7 are considered neutral.
What is meant by H, and 2H?
Explanation:
H is 1 mole of hydrogen
2H is 2 moles of hydrogen
What is the most strongest material bedrock Obsidian or diamond
What is the final temperature of a 5.0g sample of water at 25C If 832 joules of heat are added?
Answer:
64.71C
Explanation:
Given
Mass (m) = 5g
Initial Temperature (T1) = 25C
Heat (Q) = 832 joules
Required
Determine the final temperature
This question will be solved using:
Q = mc∆T
Where c = specific heat = 4.19
Substitute values in the above formula, we have:
832 = 5 * 4.19 * (T2 - 25)
832 = 20.95 * (T2 - 25)
Divide both sides by 20.95
39.71 = T2 - 25
Add 25 to both sides
39.71 + 25 = T2
T2 = 64.71C
In a decomposition reaction, NaCl might form which of the following?
A. H20
B. FeS
C. Na and Cl
D. All of the above
Answer:
THE ANSWER IS C
Explanation:
In a decomposition chemical change, NaCl might form sodium and chlorine , hence option C is correct.
What is a chemical change?Chemical changes are defined as changes which occur when a substance combines with another substance to form a new substance.Alternatively, when a substance breaks down or decomposes to give new substances it is also considered to be a chemical change.
There are several characteristics of chemical changes like change in color, change in state , change in odor and change in composition . During chemical change there is also formation of precipitate an insoluble mass of substance or even evolution of gases.
There are three types of chemical changes:
1) inorganic changes
2)organic changes
3) biochemical changes
During chemical changes atoms are rearranged and changes are accompanied by an energy change as new substances are formed.
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1) Ammonium cyanate, NH4CNO, in aqueous solution isomerizes gradually producing urea, H2NCONH2, according to the reaction
NH4CNO -> H2NCONH2
A solution was prepared by dissolving 22.9 g of ammonium cyanate in water to a volume of 1.0 liter. The evolution of the reaction, at 300k, was followed by the urea mass formed:
(a) Determine the order of the reaction
(b) Calculate the half-life of ammonium cyanate for the initial conditions of the problem
Ammonium cyanate/urea molar mass= 60g/mol
2) For the reaction
Ni(NCS)^+ + NCS Ni (NCS)2
a) Determine the Ea in direct and reverse direction using an Arrhenius graph.
b) Make, also, a qualitative diagram of energy vs. reaction coordinate indicating the values of the energies for the transposition of the barrier of direct and inverse reaction
3) Among the possible destinations of NO2 in atmospheric chemistry is the decomposition to form NO and O2. This reaction was studied at 370 C and the results obtained were as follows
based on this data, determine the speed constant K
Answer:
1(a) Second order
1(b) 44.0 minutes
2(a) Ea, forward = 85.6 kJ/mol
Ea, reverse = 60.1 kJ/mol
3) k = 9.47 M⁻¹s⁻¹
Explanation:
1(a) We are given mass of product vs time. We need to find the concentration of reactant.
For example, at t = 0 min, there is 0 g of product. Therefore, there is 22.9 g − 0 g = 22.9 g of reactant. The molar mass is 60 g/mol, so there is (22.9 g) / (60 mol/g) = 0.382 mol. The volume is 1.0 L, so the concentration is (0.382 mol) / (1.0 L) = 0.382 M.
Next, we'll graph [A] vs time, ln[A] vs time, and 1/[A] vs time.
From the graphs, we can see that 1/[A] is linear. That means the reaction is second order.
1(b) The slope of the line is equal to the rate constant k.
k = 0.0596 M⁻¹min⁻¹
The half life is:
t = 1/(k [A₀])
where [A₀] is the initial concentration of reactant.
t = 1 / (0.0596 M⁻¹min⁻¹ × 0.382 M)
t = 44.0 min
(Notice the mass of product approximately doubles from t = 20 min to t = 45 min. This confirms that the half life is about 44 minutes.)
2(a) To make an Arrhenius graph, we need to graph ln(k) vs 1/T, where T is temperature in Kelvin. We'll make two graphs, one for ka (the forward reaction) and one for kb (the reverse reaction).
The slope of each line is -Eₐ/R, where R is the gas constant. For the forward reaction:
Eₐ = -8.314 × -10300 = 85,600 J/mol = 85.6 kJ/mol
For the reverse reaction:
Eₐ = -8.314 × -7227.6 = 60,100 J/mol = 60.1 kJ/mol
2(b) Make a graph showing the energy changes as the reaction goes from the reactants to the products. The difference between the reactants and the highest point is the forward activation energy. The difference between the products and the highest point is the reverse activation energy.
3) Like problem #1, we're going to graph [A], ln[A], and 1/[A] vs time.
Once again, 1/[A] vs t is linear, so this is a second order reaction.
The rate constant is the slope of this line, so k = 9.47 M⁻¹s⁻¹.
why are divergent boundaries are also called a constructive boudary
Answer: Divergent boundaries are where two of those plates are moving away from each other. They are called constructive plates because when they move apart, magma rises up in the gap- this forms volcanoes and eventually new crust.
Explanation:
A star produces energy by:
A. expanding and contracting its magnetic field.
B. creating sunspots and releasing coronal ejections.
C. combining two atoms to form a larger atom, releasing energy.
D. splitting atoms apart, releasing energy in the form of photons.
Answer : C
Explanation:
a star produces energy by combining two atoms into one creates a powerful burst of energy
The molecular formula of butane is C4H10C4H10. It is obtained from petroleum and is used commonly in LPG (Liquefied Petroleum Gas) cylinders (a common source of cooking gas). It has two arrangements of carbon atoms: a straight chain and a branched chain.
Required:
a. Using this information, draw the structure of the tertiary butyl radical that will form upon removal of a hydrogen atom.
b. Draw the molecule on the canvas by choosing buttons from the Tools (for bonds), Atoms, and Advanced Template toolbars.
Answer:
Explanation:
Butane is an alkane with the molecular formula C₄H₁₀.
(a) It has two structural isomers (n-butane and 2-methylpropane) shown below
H H H H
| | | |
H - C - C - C - C - H
| | | |
H H H H
The structure above is n-butane
H CH₃ H
| | |
H - C - C - C - H
| | |
H H H
The structure above is 2-methylpropane and can also be referred to be a tertiary butane because the central carbon atom has 3 methyl groups attached to it as shown below.
CH₃
|
H₃C - C - CH₃
|
H
Hence, the structure of a tertiary butyl radical after loss/removal of a hydrogen atom will be
CH₃
|
H₃C - C⁻ - CH₃
NOTE: It should be noted that the central carbon becomes negatively charged after the loss of the hydrogen atom
(b) This is the practical part of the structure drawn above. The last structure illustrated above can be drawn on the canvas with the instruction provided in the question.
sxty-D
1. What fraction of the elements on the periodic table are metals?
Answer:
80%
Explanation:
Can you count how many atoms there are in the following compounds?
you are given the mass of an element, you use the periodic table to find its molar mass, and multiply the given mass by the reciprocal of the molar mass. This is Mass → Moles . Once you have moles, multiply by Avogadro's number to calculate the number of atoms. This is Moles → Atoms
Observations made during an experiment are called:
A. Data
B. Problems
C. Conclusions
D Questions
I think A
Answer:
Data
Explanation:
You are right
Determine the subunit composition of a protein from the following information:Molecular mass by gel filtration: 200 kDMolecular mass by SDS-PAGE: 100 kDMolecular mass by SDS-PAGE with 2-mercaptoethanol: 40 kD and 60 kD
Answer:
Explanation:
The protein comprises of two 60-kD polypeptides and two 40-kD polypeptides. Each one of the 40-kD chains has a disulfide-bond, which is directly bonded to a 60-kD chain.
The 100-kD units attach noncovalently to produce a protein with a molecular mass of 200 kD.
The protein consists of 200 kD in size, and the Gel filtration doesn't affect the relationship and interaction among the various subunits in the protein.
When SDS-PAGE takes place, samples are being subjected to boiling of samples and therefore undergoing denaturation conditions. The result causes disorganization in the 100 kD units.
It implies that BME is responsible for the reduction between the R1-S-S-R2 bond between 40 kD and 60 kD to R1-SH and R2-SH, resulting in separate proteins.
However, the reducing agent (BME) main task is reducing disulfide bonds in a protein.
Descibe how electronegativity and molecular shape determine the polarity of a molecule. Then describe why chemists consider relative electronegativity values and not absolute electronegativity values when determining the polarity of a bond. Also explain how a molecule with polar bonds can be non-polar overall.
Answer:
See explanation
Explanation:
Electronegativity is an idea put forward by Linus Pauling to explain the fact that in a molecule, one atom may attract the shared electrons of the bond closer to itself than the other.
Hence electronegativity is defined as the power of an atom in a molecule to attract electrons to itself.
Pauling originally described electronegativity as a relative quantity. It depends on the electronegativities of the atoms in the molecule. However, some methods have sought to measure the absolute electronegativity of a free atom.
A bond is polar when the atoms that make up the bond have a significant difference between the atoms of the molecule.
However, a molecule may possess polar bonds but may not have an overall dipole moment owing to the shape of the molecule.
For instance, CCl4 has four polar C-Cl bonds but the overall molecule is non polar because due to the fact that the molecule is tetrahedral in shape and highly symmetrical hence the individual dipoles cancel out.
50 points will give brainlyest Since thermal energy represents the total energy of the particles in an object, at the same temperature, the larger object will possess more thermal energy.
Question 3 options:
True
False
Answer:
the answer to your question is: true
Thermal energy has been the total amount of energy that has been present in the object. The thermal energy has been directly proportional to the size of the object. Thus, the statement is true, and option a is correct
What is thermal energy?Thermal energy is defined as the energy possessed by the particles of the molecules and atoms that follows the kinetic molecule theory and moves faster and collides with each other when the temperature of the system has been increased.
This type of energy has been known to be passed by the object having to be in the vicinity of the temperature. Thermal energy can flow from one substance to another due to differences in temperature.
Thermal energy has been possessed by fossil fuels like coals, and natural gases, along with electric heat,m solar heat, and geothermal heat. The thermal energy has been directly proportional to the surface area and bigger objects having more surface will be able to hold more energy.
Therefore, the statement about thermal energy and surface area is true.
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A ball of mass 0.2 kg is dropped from a height of 10 m. How much mechanical energy does it have right before it hits the ground? (Assume there is no air resistance.) Acceleration due to gravity is g = 9.8 m/s2.
Group of answer choices
0 J
10.0 J
19.6 J
25.4 J
Answer:
19.6 J
Explanation:
According to the formula:
M.E.= mgh
What is necessary to release the chemical energy from food: explosion water sunlight oxygen
Answer:
Oxygen
Explanation:
Photosynthesis releases oxygen into the atmosphere and cellular respiration uses that oxygen to release energy from food.
Why do historians analyze historical events and cause and effect relationship
What are the uses for carbon?
A balance reads an object A to be 45.1 kg. The balance reads another object B to be 33.46 kg. What is the total weight of both objects
Answer:
The total weight of both object is 78.56 kg.
Explanation:
Given data:
Mass of object A = 45.1 kg
Mass of object B = 33.46 kg
Total weight of object = ?
Solution:
Total weight of both subject must be the sum of weight of object A and B.
Total weight of objects = weight of object A + weight of object B
Now we will put the values of mass of object A and B.
Total weight of objects = 45.1 kg + 33.46 kg
Total weight of objects =78.56 kg
Thus the total weight of both object is 78.56 kg.
what have you observed when you fill in a basin with water? how do you do it?
Answer:
Cautiously and avoiding filling in the central area so that it does not overflow when filling, since being very beach makes filling difficult.
Explanation:
The basins are shallow, that is why filling is difficult, the filling must be slow, low intensity and at the edges not placing the water filling in the center of the basin.
When you fill a basin with liquid water, you can see that the water takes the shape of the container in which it is contained. This is because in the liquid state, water has molecules farther apart than in the solid state.
You can notice this property when performing an experiment with liquid and solid water.
When filling a glass, liquid water takes on the shape of a glass, and solid water, such as an ice cube, remains the same shape when placed in a glass.
Therefore, when filling a basin with water we perceive a property of the physical state of water, in liquid form. Water is one of the few substances that can be found naturally in liquid, solid and gaseous states.
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a wavelength of 4.73 x 10-7 m, and a frequency of
Answer:
Frequency =0.634×10¹⁵ s⁻¹
Explanation:
Given data:
Wavelength = 4.73×10⁻⁷ m
Frequency = ?
Solution:
Formula:
speed of light = wavelength× frequency
speed of light = 3×10⁸ m/s
Now we will put the values in formula.
3×10⁸ m/s = 4.73×10⁻⁷ m × frequency
Frequency = 3×10⁸ m/s /4.73×10⁻⁷ m
Frequency =0.634×10¹⁵ s⁻¹
s⁻¹ = Hz
Frequency =0.634×10¹⁵ Hz