Answer:
It also helps them understand how life works. It even helps them predict how new materials will behave. In 1869, Dmitri Mendeleev, a Russian chemist, proposed the periodic law and his first periodic table. He published this periodic table two years later in a textbook, The Principles of Chemistry.
Explanation:
Answer:
Dmitri Mendeleev, To summarize, the periodic table is important because it is organized to provide a great deal of information about elements and how they relate to one another in one easy-to-use reference. The table can be used to predict the properties of elements, even those that have not yet been discovered
Explanation:I have already done this
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Answer:
for number 2
Explanation:
Hydrogen. Hydrogen ignites in air. If hydrogen is present in a test tube, a lighted splint held near its mouth ignites with a squeaky pop.
Stars are _____
for most of their lives.
A) stable
B) unstable
C) unpredictable
Answer:
A. Stable
Explanation:
unless ur talking about the star in your PFP, then it's unstable xd
Answer:c
Explanation:
Glucose has formula C6 H12 O6.
Calculate the number of Oxygen atoms present in 18 g of glucose
Explanation:
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Answer:
The other person was correct =w0
Explanation:
1. What are some of the steps to the scientific method?
Answer:
Observation.
Question.
Hypothesis.
Prediction.
Experiment.
Conclusion.
Explanation:
Make an observation about something.
Form a question about that thing.
Make a hypothesis.
Predict what will happen.
Experiment.
Draw a conclusion.
Answer:
These are some steps - it usually is listed with 5 basic steps. Feedback could be the additional step.
Explanation:
Make an observation. After you make an observation ask a question. Now you will be able to form your hypothesis - what is it that you are going to test? Now, you can make a predication based on the hypothesis that you created. Make sure to test the predictions that you make. Collect data. Check to see if others have done any work like you are collecting data on. Use data to make your final decisions - based upon the hypothesis and predictions that you made. If you get confused or lost - start again and change your hypothesis. Always, always, always reflect on your results. Make sure to use DATA to back up what you find.
What must happen for water to boil at a given pressure?
O A. The water molecules must become more orderly.
O B. The water must gain thermal energy from its surroundings.
O C. The average kinetic energy of the water molecules must decrease.
D. The water must give off thermal energy to its surroundings.
Answer:
B. The water must gain thermal energy from its surroundings.
Explanation:
Boiling is the process whereby a substance is changed from a liquid state to a gaseous state due to the application of heat. For boiling to be achieved, a liquid substance must reach or exceed its boiling point, which is the specific temperature at which a specific liquid boils.
For this change of state i.e. from liquid to gas, to occur, atoms or molecules of the liquid must gain kinetic energy and move faster. However, this kinetic energy cannot be attained without a rise in temperature, which causes the molecules to gain THERMAL ENERGY or heat energy and move fast. Thermal energy is the energy that arises from a hot substance.
Therefore, for water to boil at a given pressure, it must gain thermal energy from its external surroundings, which causes its molecules to have an increased kinetic energy and move faster. This fast movement of the molecules causes the transition of phases (from liquid to gas).
9 different lab rules Explain how students will do a safe lab
Answer:
Report all accidents, injuries and breakage of class or equipment to instructor immediately.Keep pathways clear by placing extra items on the shelves or under the work tables. If under the tables make sure that these items can no be stepped on.Long hair (chin-length or longer) must be tied back to avoid catching fire.Wear sensible clothing including footwear. Loose clothing should be secure so they do not get caught in a flame or chemicals.Work quietly - know what you are doing by reading the assigned experiment before you start to work. Pay close attention to any cautions described in the laboratory exercises.Do not taste or smell chemicals.Wear safety goggles to protect your eyes when heating substances, dissecting, etcDo not attempt to change the position of glass tubing in a stopper.Never point a test tube being heated at another student or yourself. Never look into a test tube while you are heating it.Hope this helps:))
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Over a long period of time, a group of people were exposed to high degrees of UV radiation from the sun. While no one became sick immediately, doctors did predict that those exposed had an increased risk of cancer in skin cells. Which type of mutation will this exposure cause? A. acquired, harmful B. acquired, neutral C. inherited, beneficial D. inherited, neutral
Answer:
acquired/harmful
Explanation:
This type of mutation and exposure will cause indefinite problems.
What is the molar mas of zinc (Zn)? 6.02 g/mol 30.0 g/mol 48.7 g/mol 65.38 g/mol
Molar mass is defined by the ratio of the mass to the moles. The molar mass of zinc (Zn) in the periodic table is said to be 65.38 g/mol. Thus, option D is correct.
What is molar mass?Molar mass is the mass of the element or the compound in one mole of the given substance. It is denoted in units gm/ mol. The units come from the ratio of mass in grams to the moles in mol.
It is used to calculate the amount of the substance present in the mole of the substance and can be expressed as particles, like ions, or molecules with the help of Avogadro's number.
The molar mass or the atomic mass of the zinc element is denoted in the periodic table. The mass is written on the lower side of the element symbol.
Therefore, the molar mass of zinc (Zn) is 65.38 g/mol.
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Explain what a limiting reactant is and describe the process to determine the limiting reactant in the example listed below: Given 3.4 grams of x compound with a molar mass of 85 g and 4.2 grams of y compound with a molar mass of 48 g How much of compound xy can be generated 2x + y2 = 2xy
Answer:
4.36g XY
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Which is a similarity between alcohol fermentation and aerobic respiration?
I found this information:
Anaerobic respiration begins the same way as fermentation. The first step is still glycolysis, and it still creates 2 ATP from one carbohydrate molecule. However, instead of ending with glycolysis, as fermentation does, anaerobic respiration creates pyruvate and then continues on the same path as aerobic respiration.
After making a molecule called acetyl coenzyme A, it continues to the citric acid cycle. More electron carriers are made and then everything ends up at the electron transport chain. The electron carriers deposit the electrons at the beginning of the chain and then, through a process called chemiosmosis, produce many ATP. For the electron transport chain to continue working, there must be a final electron acceptor. If that acceptor is oxygen, the process is considered aerobic respiration.
Scientists believe that fermentation and anaerobic respiration are older processes than aerobic respiration.
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A substance X contains 10 gram of calcium carbonate calculate the number of mole of calcium carbonate present in X
[tex] \LARGE{ \boxed{ \rm{ \red{Required \: answer}}}}[/tex]
☃️ Chemical formulae ➝ [tex]\sf{CaCO_3}[/tex]
How to find?For solving this question, We need to know how to find moles of solution or any substance if a certain weight is given.
[tex] \boxed{ \sf{No. \: of \: moles = \frac{given \: weight}{molecular \: weight} }}[/tex]
Solution:Atomic weight of elements:
Ca = 40
C = 12
O = 16
❍ Molecular weight of [tex]\sf{CaCO_3}[/tex]
= 40 + 12 + 3 × 16
= 52 + 48
= 100 g/mol
❍ Given weight: 10 g
Then, no. of moles,
⇛ No. of moles = 10 g / 100 g mol‐¹
⇛ No. of moles = 0.1 moles
☄ No. of moles of Calcium carbonate in that substance = 0.1 moles
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Which reaction is typical neutralization reaction? H+ (aq) + OH- (aq) = H2O (g) NaCl (aq) +AgNO3(aq) = AgCl (s) + NaNO3(aq) CuO(s) +H2SO4(aq) = CuSO(4) + H2O(l) NH3(l) +H2SO4(aq) = (NH4)2SO(s)
Answer:the third
Explanation: because neutralization reaction result salt and water
When does a solar Eclipse happen, and how?
Answer:
Solar Eclipse happens when the moon gets between the sun and the earth, the moon gets all the light and blocks the earth from getting sunlight.
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The study of such concepts as motion, force, energy, matter, heat, sound, light, and the components of atoms is:
Answer:
chemistry
Explanation:
Explain where you would find the actual yield and the theoretical yield needed to calculate the percent yield of a reaction. Is the answer listed above the theoretical or actual yield?
Answer:
you could get the theoretical yield by just using the molar ratio in grams. 30g of C3H8 and the molar ratio is 1, x grams of CO2 and the molar ratio is 3. Cross multiply and you'll get 90. it's way more simple
Explanation:
are mountains physical or chemical property
Is water a physical or chemical property
is a box a physical or chemical property
is a lion a physical or chemical property
Answer:
Answer: mountains not sure
Water is chemical
Box is physical
Lion is physical
Hope this helped!!
Explanation:
How many sulfur atoms are generated when 9.42 moles of H2S react according to the following equation: 2H2S+SO2→3S+2H2O
A) 8.51 × 10^24
B) 3.78 × 10^24
C) 8.51 × 10^23
D) 9.42 × 10^23
Answer:
A) 8.51 × 10²⁴
Explanation:
1. Gather all the information
2H₂S + SO₂ ⟶ 3S + 2H₂O
n/mol: 9.42
2. Calculate the moles of S atoms
The molar ratio is 3 mol S:2 mol H₂S
[tex]\text{Moles of S} = \text{9.42 mol H$_{2}$S} \times \dfrac{\text{3 mol S }}{\text{2 mol H$_{2}$S }} = \text{14.13 mol S}[/tex]
3. Calculate the atoms of S
[tex]\text{Atoms of S } = \text{14.13 mol S} \times \dfrac{6.022 \times 10^{23}\text{ S atoms}}{\text{1 mol S}} = \mathbf{8.51 \times 10^{24}}\textbf{ S atoms}[/tex]
The sulfur atoms that should be generated is [tex]A) 8.51 \times 10^24[/tex].
Given that,
9.42 moles of H2S reacted to the given equation.Also, 1 mole for the substance contains [tex]6.022 \times 10^23[/tex] no of atoms & molecules. The calculation is as follows:[tex]= \frac{3\times 6.022\times 10^23\times 0.42}{2}\\\\= 85.0909 \times 10^23\\\\= 8.509 \times 10^24\\\\= 8.51 \times 10^24[/tex]
Therefore we can conclude that the sulfur atoms that should be generated is [tex]A) 8.51 \times 10^24[/tex].
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Which of these is the definition of the EXPLODE Physical Hazard?
A) Chemicals that are likely to be flammable and/or support a fire
B) Chemicals that release high pressure and could cause bodily injury
C) This is a potential reaction that could take place when two chemicals are
mixed together.
D) This is when a chemical breaks down and could become harmful when
handled improperly or exposed to extreme temperatures
Answer:
Explanation:
Physical hazard means a chemical for which there is scientifically valid evidence that it is a combustible liquid, a compressed gas, explosive, flammable, an organic peroxide, an oxidizer, pyrophoric, unstable (reactive) or water-reactive.
EXPLODE:
to expand with force and noise because of rapid chemical change or decomposition, as gunpowder or nitroglycerine (opposed to implode).
to burst, fly into pieces, or break up violently with a loud report, as a boiler from excessive pressure of steam.
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a)
A: Copper
B: CuO
C: [tex]\mathrm{CuSO_4}[/tex]
D: $\mathrm{CuCO_3}$
E: $\mathrm{CO_2}$
F: $\mathrm{Cu(NO_3)_2}$
b)
$\mathrm{CuO+ H_2SO_4}\rightarrow \mathrm{CuSO_4 + H_2O}$
c)
$\mathrm{CuCO_3+ 2HNO_3}\rightarrow \mathrm{Cu(NO_3)_2+ CO_2+ H_2O}$
Which of the following reactions are possible if sodium is more reactive than aluminum, 3 iron, and lead?
Reaction I: Sodium + Aluminum chloride →Sodium chloride + Aluminum Reaction II: Sodium chloride + Iron → Iron chloride + Sodium
Reaction III: Sodium + Lead chloride → Sodium chloride + lead
Answer:
Reaction I: Sodium + Aluminum chloride →Sodium chloride + Aluminum
Explanation:
Sodium being more reactive means that it will take the place of aluminium in whats called a displacement reaction and form.
Sodium chloride + Aluminum
How can you guess the name of the element using the chemical formula ?
The number of protons define what element we're dealing with.
Answer: The number of protons define what element we're dealing with.
Which criteria are responsible for deciding whether a heterogeneous mixture is a colloid or a suspension?
A.
whether its composition is uniform and transparent
B.
whether the particles remain suspended for an extended period of time
C.
whether it can be separated into simpler substances through physical separation techniques
D.
whether the ratio of components is fixed
Answer: C.
whether it can be separated into simpler substances through physical separation techniques
Explanation:
A heterogeneous mixture is colloidal if
Particles cannot be seen with a naked eye.Particles can pass through filter paperIt doesn't undergo sedimentation.A heterogeneous mixture is suspension if
Particles can be seen with a naked eye.Particles cannot pass through filter paperIt undergoes sedimentation.So, the criteria are responsible for deciding whether a heterogeneous mixture is a colloid or a suspension is "whether it can be separated into simpler substances through physical separation techniques".
So, the correct answer is "c".
The subscripts in a chemical formula are the number of
of a particular atom in one mole of the molecule.
A. reactants
B. atoms
C. moles
D. molecules
Answer:
d.molecules.its the answer.
Answer: B. molecules
Explanation:
it is the answer
The ideal gas law is a combination of all the gas laws and states that PV = nRT. The value of n stands for
A. volume.
B. mass.
C. molecular mass
D. moles.
Answer:
d
Explanation:
p is pressure, v is vo;lume, t is temperature, r is ideal gas contstant, therefore n is the moles
CH2OCH2 is an organic compound with an oxygen atom bonded between the two carbon atoms, and it is not very soluble in water. What type of compound is this?
Alcohol
Amine
Carbohydrate
Ether
Answer:
D) Ether
Explanation:
Ethers are oxygen atoms bonded between two carbon atoms. Also, I just took the test :)
CH2OCH2 is an organic compound with an oxygen atom bonded between the two carbon atoms, and it is not very soluble in water is an ether compound.
So, option D is correct one.
What is an ether?An ether is the functional group of organic compound in which one oxygen atom bonded by two alkyl group or aryl group is called an ether.
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What launched the era of modern science in the 17th century?
Answer:
Galileo Galilei
What launched the era of modern science in the 17th century? Modern science began in the 17th century, when the Italian physicist Galileo Galilei revived the Copernican view.
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Explanation:
Answer:
Explanation:
What launched the era of modern science in the 17th century? Modern science began in the 17th century, when the Italian physicist Galileo Galilei revived the Copernican view.
How is the definition of the word theory different in science versus in everyday life?
A. In everyday speech a theory is the same as a hypothesis-a statement that has (been) tested. In science a theory is a synthesis of a large body of verified information
B. In everyday speech a theory is the same as a hypothesis-a statement that has ( not been) tested. In science a theory is a synthesis of a large body of verified information
Answer:
The second option is correct.
In everyday speech a theory is the same as a hypothesis-a statement that has ( not been) tested. In science a theory is a synthesis of a large body of verified information. The correct option is B.
What is a hypothesis?A hypothesis is an explanation proposed for a phenomenon. The scientific method requires that a hypothesis be testable in order for it to be considered a scientific hypothesis.
Scientists typically base scientific hypotheses on previous observations that cannot be adequately explained by existing scientific theories.
It aids in providing a link between the underlying theory and the specific research question.
It aids in data analysis and assesses the research's validity and reliability. It serves as a foundation or proof of the research's validity.
A theory is the same as a hypothesis in everyday speech—a statement that has (or has not been) tested. A theory in science is a synthesis of a large body of verified information.
Thus, the correct option is B.
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if a moving object changes direction, its ____ would NOT necessarily
If a moving object changes its direction, its
change.
A) speed
B) velocity
C) acceleration
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the diagram shows an electrochemical cell with copper (left) and zinc (right) strips.
**Label all parts (1-9), including the solutions in each beaker and the connecting tube
**Label which cell is the cathode and which cell is the anode include the charge on each strip
**Show, or describe in detail, the flow of electrons
**Describe what type of electrochemical cell is pictured. Explain how the cell works Include the oxidation the oxidation half-reacions in your explanation
Answer:
Explanation:
1- Cathode 2- copper electrolyte solution usually (CuSO4) 3- Cu half cell 4- bulb (when lighted, shows the current is flowing) 5- Zn half cell 6- Zn electrolyte solution 7- connecting wires 8- anode (Zn) 9-salt bridge
2- the copper-(Cu) electrode is the cathode and the zinc-(Zn) electrode will be the anode. This is because the cathode is negatively charged (while Cu is positively charged, so it attracts) and the anode is positively charged (while Zn will be negative)
3- the electrons flow from the anode, where oxidization takes place, to the cathode, where reduction reactions take place.
That's the best i can do. Hope it helps.
Answer:
Explanation:
• Label all parts (1–9), including the solutions in each beaker and the connecting tube.
1. Copper strip
2. Cu2+(aq) (copper electrolyte solution or copper nitrate)
3. Cathode compartment
4. Light bulb
5. Anode compartment
6. Zn2+ (aq) (zinc electrolyte solution or zinc nitrate)
7. The connecting wires or the external circuit
8. Zinc strip
9. Salt bridge
• Label which cell is the cathode and which cell is the anode. Include the charge on each strip.
The copper strip is the cathode and the zinc strip is the anode. The anode is positively charged and the cathode is negatively charged. This is because the cathode attracts a positive charge and the anode attracts a negative charge.
• Show, or describe in detail, the flow of electrons.
The atoms from the zinc strip are oxidized into zinc ions, (the anode is where oxidation occurs). The electrons in the anode then travel through the wire to the copper strip. The electrons then merge with the copper ions in the solution creating copper metal (the cathode is where reduction occurs).
• Describe what type of electrochemical cell is pictured. Explain how the cell works. Include the oxidation and reduction half-reactions in your explanation.
This is a voltaic or galvanic cell. It works by using spontaneous oxidation-reduction reaction to generate electricity.
Zn(s) --- Zn2 + (aq) + 2e-
Cu2 + (aq) + 2e- --- Cu(s)
