Answer:
It’s true ( pure).
Explanation:
An element is defined as a pure substance that is not chemically combined with any other elements. An element comprises of mainly the sane type of atoms.
While a compound is a substance that consists of two or more elements which are chemically combined together. This is the main difference between an element and a compound.
What must a scientist do in order to develop a testable hypothesis?
O A. Be certain that the data collected will fully support the hypothesis.
B. Find out whether the hypothesis can also explain untestable
claims.
C. Make sure that no other scientist has investigated the topic
before.
O D. Determine whether it is possible to gather the necessary data.
Answer:
A
Explanation:
Be certain that the data collected will fully support the hypothesis
Answer: D. Determine whether it is possible to gather the necessary data.
Multiply:
(3.4 x 10^5)(1.2 x 10^-3)
4.08 x 10^2
4.08 x 10^-8
4.8 x 10^2
4.08 x 10^-15
Answer:
4.08 x 10^-8
Explanation:
Which of the following elements are already balanced in this equation? FeS₂ + Cl₂ → FeCl₃ + S₂ Cl₂
Fe and S are already balanced in this equation
Further explanationBalanced indicates that the number of elements in question has the same number of atoms both on the left side (the number on the reactants side) and on the right side (the number on the product side)
Even though one of the elements is said to be balanced, the chemical equation as a whole cannot be said to be balanced, because the chemical equation has several components of the constituent elements.
To balance chemical equations, a coefficient in front of the compound is usually added either in the reactants or products
Reaction
FeS₂ + Cl₂ → FeCl₃ + S₂Cl₂
From this equation, it can be shown that: the Fe and S elements are balanced because the numbers are equal both on the left and right, while the Cl elements are not yet balanced
Fe, left=1, right=1 ⇒ balanced
S, left=2, right=1 ⇒ balanced
Cl, left=2, right=5⇒ not balanced
For balanced equations:
2FeS₂ + 5Cl₂ → 2FeCl₃ + 2S₂Cl₂
Compounds X has the formula C7H15Cl; Y is C7H15Br. X undergoes base-promoted E2 elimination to give a single alkene product Z. Y likewise reacts under similar conditions to give a single alkene product that is isomeric with Z Catalytic hydrogenation of Z affords 3-ethylpentane. X readily reacts in SN2 fashion with sodium iodide in acetone. Y does not undergo a similar SN2 reaction. Propose structures for X and Y.
Answer:
See explanation and image attached
Explanation:
Let us examine the statements in the question carefully. First of all, we will discover that the products of the E2 elimination of the both compounds are isomeric. However Y does not undergo SN2 reaction as X does.
The fact that SN2 reaction does not occur in Y confirms that the bromine atom is attached to a tertiary carbon atom and SN2 reaction does not occur due to steric hinderance. Since X undergoes SN2 reaction in aprotic solvent, the chlorine atom must be attached to a secondary carbon atom.
However, E2 reactions does occur with tertiary alkyl halides when strong bases such as OH^- or RO^- are used.
The question also stated that the catalytic hydrogenation of Z affords 3-ethylpentane.
Putting all these together, the structures of X and Y have been suggested in the image attached to this answer.
Assignment
Name the type of bond present in each of the following
compounds
Aluminium Oxide ,Al3 O₂)
Answer:
[tex]\boxed {\boxed {\sf Ionic \ bond}}[/tex]
Explanation:
First, let's look at the Periodic Table.
We see that aluminum is a metal, while oxygen is a non-metal.
Now, let's recall three types of bonds
Ionic: typically forms between a metal and a non-metal Covalent: usually forms between non-metals Metallic: tends to form with metalsSince we have a metal (Al) and a non-metal (O), aluminum oxide must have an ionic bond.
The following equation is balanced according to the Law of Conservation of Mass:
2 NO + O2 → 2 NO2
True
False
What kind of reaction happens when two compounds switch elements?
A. A double-replacement reaction
B. A single-replacement reaction
C. A synthesis reaction
D. A decomposition reaction
Answer:
A
Explanation:
Write down the names of compounds represented by the following formulae:
a. Al2(SO4)3
b. CaCl2
c. K2SO4
d. KNO3
e. CaCO3
Hellp plss
The compounds have been formed by the combination of molecules and atoms. The names are a. aluminum sulfate, b. calcium chloride, c. potassium sulfate, d. potassium nitrate, and e. calcium carbonate.
What is the chemical formula?The chemical formula has been defined as the representation of the chemical compound or molecules with the aid of symbols, letters, and coefficients to show the proportions, arrows, parentheses, signs, etc.
The chemical formulas are named as:
Al₂(SO₄)₃ - aluminum sulfate. It has been used in purifying water, sewage treatment, tanning, paper industries, etc.CaCl₂ - calcium chloride. It is an ionic compound used in making electrolytes and sports drinks.K₂SO₄ - potassium sulfate. It has been used for making fertilizers for tobacco and vegetable crops.KNO₃ - potassium nitrate. It is an oxidizer used for making explosives and fertilizers.CaCO₃ - calcium carbonate. It is used as a dietary product to satisfy the needs for calcium and vitamin D for bone strengthening and formation.Learn more about chemical formulas, here:
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What is the mass of 2.23 x 10^23 atoms of sulfur?
Answer: 32.07 g/mole
Explanation:
1 mole of sulfur contains 6.022 ×10^23 atoms
1 mole is equal to 32.07 g
6.022 ×10^23 atoms = 32.07
Which pair of objects is experiencing the greatest gravitational force
Answer:
Explanation:
Is that the question
Answer:
If it's between human and tennis ball, human and dog, human and building, human and earth.
It would be HUMAN AND EARTH
Explanation:
I took the test and got that.
Which chemical equation below is balanced to correctly represent the Law of Conservation of Mass?
Answer:
The 3rd equation.
Cl2 + 2NaBr —> 2NaCl + Br2
Explanation:
The law of conservation of matter (mass) states that matter can neither be created nor destroyed during a chemical reaction but can be transferred from one form to another. This implies that unbalanced chemical equation shows that matter (mass) has been created or destroyed.
Now, we shall determine which equation is balanced as follow:
1. 2Cl2 + NaBr —> 2NaCl + Br2
Reactant >>>>>>>> Product
4 Cl >>>>>>>>>>>> 2 Cl
1 Na >>>>>>>>>>>> 2 Na
1 Br >>>>>>>>>>>> 2 Br
Thus, the equation is not balanced.
2. Cl2 + NaBr —> NaCl + Br2
Reactant >>>>>>>> Product
2 Cl >>>>>>>>>>>> 1 Cl
1 Na >>>>>>>>>>>> 1 Na
1 Br >>>>>>>>>>>> 2 Br
Thus, the equation is not balanced.
3. Cl2 + 2NaBr —> 2NaCl + Br2
Reactant >>>>>>>> Product
2 Cl >>>>>>>>>>>> 2 Cl
2 Na >>>>>>>>>>> 2 Na
2 Br >>>>>>>>>>>> 2 Br
Thus, the equation is balanced.
From the illustration made above only the 3rd equation is balanced. And this is in line with the law of the Conservation of matter (mass) as matter (mass) was not created nor destroyed during the chemical reaction but was transferred to other forms.
The map below shows the top view of a meandering stream as it enters a lake.
At which point, along the stream, are erosion and deposition?
A.
Erosion occurs at points B and D, deposition occurs at A and C
B.
Erosion occurs at points A and B, deposition occurs at C and D
C.
Erosion occurs at points A and C, deposition occurs at B and D
D.
Erosion occurs at points B and C, deposition occurs at A and D
Answer:
c
Explanation:
The erosion starts at A moving sand or soil, then drops it at B-D.
A crystal is made up of _____
Explanation:
Atoms of the same element or atoms of different elements.
We cooleda water bottle so the volume was lowered to .050 L, then we heated it to 373 K and thevolume increased to .10 L. What was the initial temperature?
Answer:
[tex]186.5\ \text{K}[/tex]
Explanation:
[tex]V_1[/tex] = Initial volume = 0.05 L
[tex]V_2[/tex] = Final volume = 0.1 L
[tex]T_1[/tex] = Initial temperature
[tex]T_2[/tex] = Final temperature = 373 K
From the ideal gas law we have
[tex]PV=nRT[/tex]
So
[tex]V\propto T[/tex]
[tex]\dfrac{V_1}{V_2}=\dfrac{T_1}{T_2}\\\Rightarrow T_1=\dfrac{V_1}{V_2}\times T_2\\\Rightarrow T_1=\dfrac{0.05}{0.1}\times 373\\\Rightarrow T_1=186.5\ \text{K}[/tex]
The intial temperature is [tex]186.5\ \text{K}[/tex].
Screenshot very easy
1. option B
2. ground state Fe : [Ar] 4s² 3d⁶
Further explanationAufbau rule
Electrons occupy orbitals of the lowest energy level
Charging electrons in the sub-shell uses the following sequence:
1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁶, 5s², 4d¹⁰, 5p⁶, 6s², etc.
So the correct choice of answer is B.
Ground state is the state of electrons filling skins with the lowest energy levels.
Excited state is the state of electrons which occupy a higher energy level
The atomic number of Fe = 26, so electrons=26
Ground state configuration of Fe : [Ar] 4s² 3d⁶ or
1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d⁶
Answer:
d
Explanation:
Which term refers to the sum of the kinetic energy of all the particles in an object?A.Potential energyB.Thermal energyC.TemperatureD.Heat
plzz hurry
Answer:
It’s the other answer, thermal energy
Explanation:
I hope y’all get a good grade
Thermal energy refers to the sum of the kinetic energy of all the particles in an object. Hence, the correct option is B.
Thermal energy is a form of internal energy associated with the random motion and vibrations of atoms and molecules within a substance. It is directly related to the temperature of the object, as the temperature is a measure of the average kinetic energy of the particles. The higher the temperature, the greater the thermal energy of the object.
Potential energy (A) refers to the energy that an object possesses due to its position or state, such as gravitational potential energy or elastic potential energy.
Temperature (C) is a measure of the average kinetic energy of the particles in a substance and is not the sum of the kinetic energy of all the particles. However, it is related to thermal energy as it provides information about the average kinetic energy.
Heat (D) refers to the transfer of thermal energy from one object to another due to a temperature difference. It is not the sum of the kinetic energy of the particles in an object but rather the energy transfer between objects with different temperatures.
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Atoms and elements are examples of
Answer:
A particular atom will have the same number of protons and electrons and most atoms have at least as many neutrons as protons. An element is a substance that is made entirely from one type of atom. For example, the element hydrogen is made from atoms containing just one proton and one electron.
Any 1 help with Chemistry here??
How do you think dolphins find food in dark water, especially if
what they are looking for does not make any noise? What other
sense might they use to "see” without using their eyesight?
Answer: Dolphins use the sense (sound) to find food in dark water.
Explanation: Echolocation allows dolphins to “see" by interpreting the echoes of sound waves that bounce off of objects near them in the water. To echolocate objects nearby, dolphins produce high-frequency clicks. ... This information is critical for dolphins to find food and navigate in dark or murky waters.
How many moles of KCl are contained in this solution?
0.486 L of a 2.0 M KCl solution
Answer:
0.972mol
Explanation:
Given parameters:
Volume of Solution of KCl = 0.486L
Molarity = 2.0M
Unknown:
Number of moles of KCl in solution = ?
Solution:
To find the number of moles of KCl in this solution, use the expression below;
Number of moles = molarity x volume
Insert the parameters and solve;
Number of moles = 0.486 x 2 = 0.972mol
Identify each statement below as an example of science or pseudoscience.
If food dropped on the floor is picked up within 5 seconds, it is okay to eat.
science or pseudoscience
Answer: pseudoscience
Explanation:
Edge 2020
Answer: pseudoscience
Explanation: It is an opinion that is subjective.
Why is it important to know the weather?
Answer:
so you can dress based on how hot or cold it's gonna be outside
1. an ancient study or art which attempted to combine science and philosophy to solve worldly problems alchemy 2. a homogeneous mixture of elements with metals to form metallic solids alloy 3. the simplest unit of an element that still retains the properties of that element compound 4. two or more elements joined together such that the elements have lost their individual identity element 5. a primary substance that cannot be divided into separate substances metal 6. the group of elements that are good conductors of electricity and heat atom 7. the group of elements that are poor conductors of electricity and heat
Answer:
1. Alchemy
2.Alloy
3.Atom
4.Compound
5. Element
6. Metal
7. Non metal
Explanation:
1. An ancient study or art which attempted to combine science and philosophy to solve worldly problems is alchemy
2. A homogeneous mixture of elements with metals to form metallic solids is an alloy
3. The simplest unit of an element that still retains the properties of that element compound is an atom.
4. Two or more elements joined together such that the elements have lost their individual identity element is called a compound
5. A primary substance that cannot be divided into separate substance is an element
6. The group of elements that are good conductors of electricity and heat is called a metal
7. The group of elements that are poor conductors of electricity and heat are called non metals.
Before J.J. Thomson began gathering evidence about electrons in 1897, what did scientists know about atoms?
Answer: Scientists generally thought atoms were the smallest particles that could not be broken down any further.
Explanation: Trust me
To see the number of atoms of an element in a given molecule we need to multiply stoichiometry to the number that is written on the foot of the element that is stoichiometry. Scientists generally thought atoms were the smallest particles that could not be broken down any further.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided. Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit.
In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge. Neutron is neutral that is it has no charge. So overall the charge of nucleus is due to only proton, not by neutron.
Before J.J. Thomson began gathering evidence about electrons in 1897. Scientists generally thought atoms were the smallest particles that could not be broken down any further.
Therefore, Scientists generally thought atoms were the smallest particles that could not be broken down any further.
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How many moles are in 16.2 grams of lithium ?
Answer:
6.941 moles
Explanation:
Help please I don’t know
Answer:
I don't EXACTLY know but hopefully the description below helps you find the answer!
Ionic bonding is a type of chemical bond in which valence electrons are lost from one atom and gained by another. This exchange results in a more stable, noble gas electronic configuration for both atoms involved. An ionic bond is based on attractive electrostatic forces between two ions of opposite charge.
Explanation:
Who uses Ionic compounds?
Use the periodic table to select which type of bond is present and which of the listed properties is most likely for each substance.
A =
B =
Cu3Zn2
O2
Answer:
A :metallic
B :conducts electricity as a solid
C :covalent
D :does not conduct electricity
Explanation:
Answer:
A = ✔ metallic
B = ✔ conducts electricity as a solid
C = ✔ covalent
D = ✔ does not conduct electricity
Explanation:
edge 2023
The diagram represents a section of Earth that a paleontologist, a
scientist who studies fossils, has been working with for years. Which
statement correctly describes this diagram?
a
b
Layer W contains fossils of organisms that existed on Earth after the organisms found in layers U and R.
Layer U contains fossils of organisms that are older than the organisms found in layer R.
Layers W and U contain fossils that are animal species.
Layers R and W contain fossils that are both types of plant species.
C с
Od
Answer: A
Explanation:
Question:
A. Does this picture show a physical or chemical change? How do you know?
B. Does this picture show a physical or chemical change? How do you know?
Answer:
A. Chemical
B. physical
Explanation: