Help answer these chemistry questions
Answer:
45th answer is pure and properties 42 is periodictable
Two samples of carbon come into contact. A heat transfer will occur between sample A and sample B. What must be true for heat to transfer from sample A to sample B
Use the Periodic Table to find molar mass of water. Sodium hydroxide (NaOH) and hydrochloric acid (HCl) react to form sodium chloride (NaCl) and water according to the equation: NaOH HCl → NaCl H2O What mass of water forms when 2. 75 Ă— 10â€""4 mol NaOH reacts completely? 2. 75 Ă— 10â€""4 mol NaOH = g H2O.
Considering the reaction stoichiometry, 0.00495 grams of water is produced when 2.75×10⁻⁴ moles of NaOH reacts completely.
Sodium hydroxide (NaOH) and hydrochloric acid (HCl) react to form sodium chloride (NaCl) and water. So, the balanced reaction is:
NaOH + HCl → NaCl + H₂O
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
NaOH: 1 moleHCl: 1 moleNaCl: 1 moleH₂O: 1 mole
In the periodic table, you can find the molar mass of the elements, also called atomic mass or atomic weight. So, to calculate the molar mass of a compound, you must add the molar mass of the elements of the compound multiplied by the times they appear in the compound.
So, in the case of water:
H₂O= 2× 1 g/mole + 16 g/mole
H₂O= 18 g/mole
Then, if by stoichiometry of the reaction 1 mole of water is produced, the mass of water produced is calculated as:
mass H₂O= 1 mole× 18 g/mole
mass H₂O= 18 g
Then you can apply the following rule of three: if by stoichiometry 1 moles of NaOH produce 18 grams of H₂O, 2.75×10⁻⁴ moles of NaOH will produce how much mass of H₂O?
[tex]mass of H_{2} O=\frac{2.75x10^{-4} moles of NaOHx18 grams of H_{2} O}{1 mole of NaOH}[/tex]
mass of H₂O= 0.00495 grams
In summary, 0.00495 grams of water is produced when 2.75×10⁻⁴ moles of NaOH reacts completely.
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brainly.com/question/16487206?referrer=searchResults brainly.com/question/14446695?referrer=searchResults brainly.com/question/11564309?referrer=searchResults brainly.com/question/4025026?referrer=searchResults brainly.com/question/18650135?referrer=searchResultsWhich of the compounds in the table below is listed in the wrong colum?
Answer: C
Explanation: This is because of a nice thing called guessing
When sodium is put in water, the metal floats on the surface and reacts to form sodium
pls help asap
Answer: Sodium also floats on the surface, but enough heat is given off to melt the sodium (sodium has a lower melting point than lithium and the reaction produces heat faster) and it melts almost at once to form a small silvery ball that dashes around the surface.
Explanation:
Answer:
hydroxide.
Explanation:
Alkali metals are in group 1 of the Periodic Table. They are on the left of the Periodic Table. These are the alkali metals as follows:
LithiumSodiumPotassiumRubidiumCaesiumFranciumWhen alkali metals react with water they make alkaline solutions, so the universal indicator turns people and they produce hydrogen and a metal hydroxide. When sodium is put in water, the metal floats on the surface it reacts to form sodium hydroxide and hydrogen.
Which of the following is an example of genetic engineering?
1.The sweetest honeydew melons are selected and the seeds extracted and planted for next year’s crop.
2.The strongest animals in a population survive and reproduce.
3.An exact replica of a frog is created from a body cell.
4.A gene is introduced into salmon to make them grow twice as fast.
Answer:
4. A gene is introduced into salmon to make them grow twice as fast.
Find the density of an 8 gram rock if the water in a graduated cylinder rises from 25.0 mL to
29.0 mL when the rock is placed in to the graduated cylinder.
To measure the density of the stone placed in a graduated cylinder let us follow these steps bellow
Measure the volume of water poured into a graduated cylinderPlace the object in the water and remeasure the volume. The difference between the two volume measurements is the volume of the object. Divide the mass by the volume to calculate the density of the object.We know that the formula for density is given as
Given data
Mass = 8gram
Initial Volume of water in cylinder = 25mL
Final Volume of water in cylinder = 29mL
Hence the volume of the rock = 29-25 = 4mL
Therefore the density of the rock = 8/4 = 2 g/mL
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How can you find each of the 4 blood vessels when dissecting?
Answer:
that's a weird question
Explanation:
why do you need to know that?
Why does all matter contain thermal
energy?
A. Because particles stop moving
B. Because all matter is hot
C. Because particles can never stop moving
D. Because all matter is cold
Answer:
The answer is C. Because particles can never stop moving
Explanation:
"All matter has thermal energy, even matter that feels cold. That's because the particles of all matter are in constant motion and have kinetic energy."
3. Explain why the statement "electrons are always located close to the nucleus of an atom" is not really accurate,
Answer:
Electrons are stored in different electron shells with the nucleus in the center. Depending on the size of the element, the electrons may need more shells, making the electrons further away from the nucleus.
Explanation:
Atoms contains nucleus in its center and electron that revolve around the atom in fixed orbit. the statement "electrons are always located close to the nucleus of an atom" is not really accurate.
What is atom?Atom is the smallest particle of any element, molecule or compound. Atom can not be further divided.
In the nucleus, proton and neutron are present. Electron has -1 charge while proton has +1 charge.
Electrons always move in fixed orbit around the nucleus with a particular force. Electrons may or may not be close to the nucleus. Depending on the size of the element, the electrons may need more shells, making the electrons further away from the nucleus.
Therefore, the statement "electrons are always located close to the nucleus of an atom" is not really accurate.
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FeCl3
+
NaOH →
Fe(OH)
+
Naci
-
balance plzzzz help I live give u the brainliest
Select all the statements that correctly describe a solution. Multiple select question.
A. A solution is a mixture of substances dissolved in water.
B. A solution may have more than one solute.
C. Not all solutions are liquid.
D. A solution is a homogeneous mixture of two or more substances.
E. The solute is the substance present in the largest quantity.
Answer:
B, D, C
Explanation:
the solution may have more than one solute, a solution is a homogenous mixture of 2 or more substances and not all solutions are liquid
A solution is formed by the mixture of substances dissolved in water. There may have more than one solute. Not all solutions are liquid but there exists solid solutions too. Hence, options A, B, C are correct.
What are solutions?A solution is a combination of a solvent and a solid solute. The solute can be completely dissolved in the solvent and can have a partial solubility.
Water is a good solvent which dissolve majority of compounds. But there are other solvents too forming solution with suitable solutes. Solutions can be homogenous or heterogenous. Homogenous solutions are forming one phase and the solute particles are uniformly arranged.
Heterogeneous solutions are those where the solute particles are arranged in a non-uniformity and they form a different phase from the solvent.
There can be more than one solute in a solution provided that the solute can be of miscibility with each other.
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CORRECT ANSWER WILL GET BRAINLIEST
Is the following nuclear equation balanced?
A. yes
B. no
Answer: B. no
Explanation:
during hybridization ______.
A) nature selects which organisms will survive and reproduce.
B) the nucleus of a cell is removed.
C) two organisms with desired traits are bred.
D) a single beneficial trait is bred into a species.
Answer:
option C two organisms with desired traits are bred
Consider the substances quartz (SiOs), gold (Au), and nitrogen gas (N2). If possible, use the terms
molecule and compound to describe each substance. If one or more of the substances cannot be
described by the terms molecule and compound, explain why not.
Answer:
Silicon Dioxide is a compound usually referred to as Quartz, it's a crystalline sort of material that is commonly found and used for equipment and furniture (like tables for example). Their molecular geometry is of tetrahedral shape (how their bonds look like and such)
Gold is an element that is a transitional metal that is quite malleable (able to hammer it to sheets) and is ductile (can be made into wires). As you probably have guessed, gold is used a lot for jewelry due to its lustrous appearance, and the fact that it can't corrode as well as its rarity. Due to it not being able to corrode, it's pretty useful in circuitry as it requires less management unlike elements with higher electrical conductivity like copper or silver. However gold is pretty costly so it's not often relied on for technology and mostly just used for show instead.
N2 or nitrogen gas, may seem like a compound for people new to chemistry but is actually just a diatomic molecule, meaning they are composed of only 2 atoms. So elements that are diatomic are commonly found with only 2 atoms (Oxygen gas for example, or Hydrogen gas) Nitrogen is part of the "magnificent seven" (the elements which are diatomic". Nitrogen is essential for a lot of living things (aside from us), and since they are the most abundant material in our air (78% of air is Nitrogen), there's plenty of life growing.
Compound and elements are differ from each other. Silicon dioxide ( SiO₂ ) is compound , gold ( Au ) is element and nitrogen gas ( N₂ ) is compound.
What is difference between molecule and elements ?Elements are always made-up of only one type of atom. Molecule is made up of more than one type of atom. Silicon dioxide is a compound, which is crystalline in nature. Their molecular geometry is of tetrahedral shape.
Gold is an element that is a transitional metal that is quite malleable and is ductile. Gold ( Au ) is used a lot for jewelry. Nitrogen gas is compound . It is diatomic in nature, So elements that are diatomic are commonly found with only 2 atoms.
Hence, silicon dioxide is compound, gold is element, and nitrogen gas is also compound.
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SEP Construct Explainations: Explain how a substance's flammability can indicate a chemical change.
Answer:Wood for barbucue.
Explanation:
A ball rolls down a hill. It starts with velocity of 2 ms. After 2 seconds, the ball has a velocity of 12 ms. What is the acceleration of the ball? 2 ms2 4 ms2 5 ms2 7 ms2
Answer:
5 ms2
Explanation:
The acceleration of the ball is 5 ms2.
What is acceleration?Acceleration is the rate at which an object's velocity with respect to time changes. It is a vector quantity to accelerate (in that they have magnitude and direction). The direction of the net force acting on an object determines the direction of its acceleration.
The acceleration of the car in its present direction of motion is referred to as a linear acceleration (or tangential acceleration in circular motions), and the passengers on board feel a force pressing them back into their seats as a result.
The acceleration that is used to change direction is referred to as radial acceleration (or centripetal acceleration in circular travels), and the reaction that the passengers feel is a centrifugal force.
Therefore, The acceleration of the ball is 5 ms2.
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New research shows that a red food colouring with an R value of 0.62 (when a particular solvent and temperature are used) could be dangerous to certain people. Samples of food colouring from two different red sweets were collected and the chromatogram bolow was produced. For each of the sweets, state and explain whether or not you would recommend that the sweets are taken off the market based on this research,
It is recommended only for the second type of candy to be taken off the market.
Based on the background information, if a candy shows a 0,62 Rf value in the chromatography it is considered potentially dangerous, and therefore it should be taken off the market.
The Rf value is calculated using the following formula:
Rf = Total distance traveled by a component/ Total distance from the pencil line to the solvent frontNow, let's find out if any of the components has an Rf equal to 0,62.
Note: To determine the distances I measured the image using a ruler and you can do the same, this will not alter the results.
Sample 1Total distance traveled by the component: 6cmTotal distance: 7 cmRf : 6 cm/ 7 cm = 0.852. Sample 2
Total distance traveled by the component: 4.34cmTotal distance: 7 cmRf : 4.34 cm/ 7 cm = 0.62This means sample 2 has the 0.62 Rf value and therefore it needs to be taken off the market.
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This chemical equation is balanced.
F2 + 2NaBr
2NaF + Br2
How does the balanced chemical equation show the conservation of matter
in this chemical reaction?
A. There are fewer Na atoms in the reactants than in the products.
B. The number of Fatoms in the reactants equals the number of F
atoms in the products.
C. The compound NaF is a substance that is different from the
compound NaBr.
D. There are more Br atoms in the reactants than in the products.
calculate the molarity of a 50.0 ml of a 0.150 m hcl solution when 30.0 ml of water is added.
Answer:
0.09375 M
Explanation:
You want to use the following equation:
M1*V1=M2*V2
Then plug in the 50ml to V1 and 0.15M to M1 and 80ml to V2 (add the 50 and 30). The next thing you want to do is change the mL to liters, since Molarity is moles/liter. Once that is done, solve algebraically for answer.
** Also don't forget to capitalize the M when you mean Molarity, because it is different than m.**
Hope this helps!
Did the flower used in this investigation come from a plant that reproduces sexually or asexually? Explain your answer. (If u don’t know the answer don’t answer.) (No picture) (I didn’t know what category)
Answer:
Asexually
Explanation:
Plant's cannot reproduce sexually
the idea of arranging the elements in the periodic table
Elements are arranged from left to right and top to bottom in order of increasing atomic number. Order generally coincides with increasing atomic mass. The rows are called periods.
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How many grams are in 4.1 mole sample of CO?
Not every earthquake has a(n) ______, but every earthquake has _____that occur in _____ the mainshock.
1.
Aftershock
Foreshock <------
2.
Aftershock <-------
Foreshock
3.
Places far away from
The Same place as <------
Am i right?
Not every earthquake has a(n) Foreshock, but every earthquake has an Aftershock that occurs in the Same place as the mainshock.
What is an earthquake?
An earthquake is defined as a natural disaster in which there are tectonic plates that are present on the earth's crust collides with each other.
An Earthquake can be minor as well as natural depending upon the frequency it causes the damage. Earthquake is the Shaking of Earth and was much destruction of the economy and manpower.
Surroundings are being disturbed like trees will fall, and buildings will collapse which will cause damage to the economy as well as to human life.
Foreshock is the before shop which happens before the earthquake and aftershock is the other socks that happen after the earthquake
Thus, the correct options are 1. Foreshock, 2. Aftershock, 3. The Same place as.
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Help. 50 points. Need honest answers.
Answer:
ok
Explanation:
Calculate the Enthalpy for the following reaction using the listed thermochemical equations:
Please help
Answer:
896.5
Explanation:
You want to manipulate each equation individually.
First Equation: Keep it how it is, because N2 is the same in the final and 1st equation
Second Equation: Multiply the enthalpy by 4 because you want the H2Os to be equal
Third Equation: Switch the sign of the enthalpy because you want toe H2O2 on the other side of the equation, and multiply by 2 to match the coefficient
Answer:
this might be of help to u
Which of the following is not an ingredient for photosynthesis?
A. Oxygen
B. Carbon dioxide
C. Light energy
D. Vinegar
Answer:
d
Explanation:
......................
Answer:
D. vinegar
Explanation:
Hope this helps you!!
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help me please i dont understand
Answer:
1. Dissolving powder in milk - Chemical
- It is chemical because the milk has changed on a molecular level
2. Toasting bread - Chemical
- It is chemical because adding heat to the bread cooks it, therefore
changing it on a molecular level
3. Melting cheese - Physical
- It is physical because the physical appearance was the only change
4. Slicing apples or bannanas - Physical
- It is physical because the physical appearance was the only change
5. Frying an egg - Chemical
- It is chemical because new particles were formed
6. Milk souring - Chemical
- It is chemical because it is forming a new product (lactic acid)
Explanation:
Physical Change occurs when the particles of a substance become rearranged, but do not change into different particles.
Chemical change occurs when a new substance is formed. This process is irreversable.
Answer:
give the preson above brainly bc there right
Explanation:
the name of element P
Answer:
phosphorus
Explanation:
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1. Explain the difference between genetic, environmental, social, and pathogenic factors.
2. How do pathogens spread?
3. How can we, as humans, prevent transmission of pathogens?
4. List three ways the environment can affect personal health.
Answer:They can be spread through skin contact, bodily fluids, airborne particles, contact with feces, and touching a surface touched by an infected person.
Immunise against infectious diseases.
Wash and dry your hands regularly and well.
Stay at home if you are sick.
Cover coughs and sneezes.
Clean surfaces regularly.
Ventilate your home.
Prepare food safely.
Practise safe sex.
Explanation: