Answer:
CaCl,2
the 2 goes to the bottom right side
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 most strongest material bedrock Obsidian or diamond
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.
Which of the following is an example of an endothermic reaction?
!!! thank u!!
Answer:
Combustion
Explanation:
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.
whai is the maining of science?
Answer:
the intellectual and practical activity encompassing the systematic study of the structure and behaviour of the physical and natural world through observation and experiment.
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.
please Mark as brainliest and follow
Answer:
bent and trigonal planar
Explanation:
what energy transformations does microwave have
Answer:
radiant energy
Explanation:
microwaves convert electrical energy into radiant energy
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.
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.
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
Why do historians analyze historical events and cause and effect relationship
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.
Learn more about chemical change,here:
https://brainly.com/question/23693316
#SPJ2
Observations made during an experiment are called:
A. Data
B. Problems
C. Conclusions
D Questions
I think A
Answer:
Data
Explanation:
You are right
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:
What are the uses for carbon?
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:
Easy Question. Will mark brainliest
Carbon combines with oxygen to form two compounds, carbon monoxide and carbon dioxide. Based on the law of multiple proportions, describe how the proportions of oxygen in the two compounds relate to each other.
Answer:
Their components
Explanation:
It's simple enough, the components in carbon dioxide and carbon monoxide both have at least one carbon and one oxygen atom. However, they differ because their amount in the molecules is different, and that is because of their covalent bonds. Carbon dioxide has to double electron bonds while carbon monoxide has a rare triple electron bond.
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.
what is gravity and weight please answer
Weight is the force of gravity on an object. Weight depends on the strength of the gravitational field the object is in and the mass of the object. ... Mass is constant anywhere in the universe, whereas weight depends on the gravity where the object is present (Earth, the moon, Jupiter, etc.).
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
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.
Learn more here:
https://brainly.com/question/23650420
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.
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
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:
What is the mass in grams of 381 mL of ethylene glycol?
Answer:
38
Explanation:
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
sxty-D
1. What fraction of the elements on the periodic table are metals?
Answer:
80%
Explanation:
What type of energy is stored in fuels such as gasoline and batteries
Answer:Chemical energy
Explanation:Chemical energy is energy stored in the bonds of atoms and molecules. Batteries, biomass, petroleum, natural gas, and coal are examples of chemical energy. Chemical energy is converted to thermal energy when people burn wood in a fireplace or burn gasoline in a car's engine.
The type of energy which is stored in fuels such as gasoline and batteries is chemical energy.
What is chemical energy?
Energy which is stored in the chemical bonds of chemical compounds is called chemical energy.Chemical energy is released during the occurrence of chemical reaction.Reactions wherein energy is given out in the form of heat is called exothermic reactions.
Chemical energy can be converted to other forms of energy like electrical energy during the process of electrolysis and to thermal energy as in the case of thermal engines.
It can also be converted to kinetic energy during explosions . It is stored in batteries, coal, biomass, food, vehicle air bags,etc.
Learn more about chemical energy,here:
https://brainly.com/question/30288262
#SPJ2
“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.