Answer:
May be 119 elements are artificially made.
Answer:
119 elements are artificially made...
Why is elemental zinc considered a pure substance?
Select one:
It is a metal.
It is a mixture of different atoms.
All elements are considered pure substances.
It must be created in a lab.
Answer: C... Because Zinc is made of only one type of atoms.
Explanation: All elements are made of one type of atom. Pure gold is made out of only gold atoms, silver out of only silver atoms, etc.
Which of the following is the correct word equation for the reaction described below?
Calcium hydroxide and hydrogen gas are produced by the reaction of calcium hydride and water.
calcium hydride + hydrogen → calcium hydroxide + water
calcium hydride + water → calcium hydroxide + hydrogen
calcium hydroxide + hydrogen → calcium hydride + water
calcium hydroxide + water → calcium hydride + hydrogen
Explanation:
calcium hydride + water → calcium hydroxide + hydrogen
hope it helps!
Answer:
B
Explanation:
got it right on edg
What type of boundary exists along the coast of California?
Answer:
I exist ;-;
Explanation:
23. Soluble salts can be prepared using
the following methods except by
A. action of dilute acids on
metals.
B. action of dilute acid on an
insoluble base.
C. direct combination of
constituent elements.
D. neutralization reactions.
E. precipitation from solutions,
help ple*zzzz*zzz*
Answer:
I think crystallization is a write answer for this question
Explanation:
but according to this (E is the write answer)
How many atoms are present in 1.4 grams of aluminum?
Answer: 3.2x10^23
Explanation:
Start by finding the molar mass of aluminum.
Then turn grams into moles by dividing grams of substance by molar mass. 1.4g÷26.98g
Then multiply that by 6.022x10^23 atoms. 0.0519x6.022x10^23
You can use dimensional analysis to solve this type of problem.
What is the atomic number of this element?
Answer:
27
Explanation:
Multiple choice-- 16 pts!
Two moles of aluminum chloride are dissolved in two liters of water.
How does the vapor pressure of the water change?
It increases because aluminum and chloride ions displace water molecules, which escape into the gas phase.
It first decreases as aluminum chloride attracts the water molecules, but it then increases as dissolving completes and starts to push water molecules out.
It decreases because nonvolatile aluminum and chloride ions now occupy some of the volume of the system.
Answer: It decreases because nonvolatile aluminum and chloride ions now occupy some of the volume of the system.
Explanation:
Vapor pressure of a liquid is defined as the pressure exerted by the vapors in equilibrium with the liquid/solution at a particular temperature.
So, when a non-volatile solute is added to a solvent then its molecules align at the surface of liquid. As a result, less number of solvent molecules will escape from the solution. Thus, there will be decrease in vapors and thus the vapor pressure decrease.
The relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.
what is the formula for this bond?
What is not a correct description of a chemical element?
a. It is made of one type of atom.
b. It is the simplest substance of all matters.
c. Its atoms can be chemically separated.
d. Its atoms can be physically separated.
Answer:
b
Explanation:
because it is the simplest substance of all matters
Is a bell pepper a substance
How does Global warning affect the ocean
Answer:
The ocean absorbs most of the excess heat
Explanation:
Increasing ocean temperatures affect marine species and ecosystems. Rising temperatures cause coral bleaching and the loss of breeding grounds for marine fishes and mammals.
Explain why a) Kl (potassium iodide) dissolves in water, but b) it will not dissolve in
hexane.
Answer:
Explanation: Brief description of demonstration
Three clear liquids form three distinct layers in a cylinder. Iodine crystals sprinkled on the top layer sink and form pink solutions with the top and bottom layers but do not dissolve in the middle. When the liquids are mixed, two layers form: a pink layer on the bottom, and a colorless layer on top. When white potassium iodide crystals are added and the liquids are mixed again, the colorless layer turns yellow.
Concepts illustrated:
• Phases and phase boundaries (surfaces)
• Density
• Polar/non-polar (hydrophilic/hydrophobic) interactions
• Solubility, miscibility
• Chemical reaction
• Extraction
• [Solution and emulsion]
Materials
• Clear glass reaction cylinder or gas-washing bottle, at least 200 mm tall, with ground glass stopper (A cylindrical container is preferable to a separatory funnel for this experiment. The stopper must be non- reactive, and, to prevent a potentially dangerous pressure build-up, the stopper must be easily released. For a very small class, a large test tube with a suitable stopper is adequate. )
• Equal volumes of chloroform, water, and hexane (The volume of each liquid should be a little more than one-fourth the volume of the cylinder.)
• Iodine crystals and small spatula
• Potassium iodide crystals and medium spatula
Preparation
Work in a hood. Pour the chloroform into the reaction cylinder. Add the water and allow the liquids to separate completely. (If necessary, speed the process by holding the cylinder vertical and gently swirling the solution with a circular motion.) Tip the cylinder and pour the hexane slowly down the side to prevent mixing. Close the cylinder and set it aside, away from sources of heat, until time for the demonstration.
Answer:It forms single phase mixtures (solutions) with other polar and ionic substances. ... Since water is less dense than this non-polar mixture, the bubbles rise to the top. Potassium iodide, an ionic compound, dissolves easily in water but does not dissolve in chloroform and hexane.
Explanation:
20. Sudan III is used to test for
A. cellulose.
B. fats and oils.
C. glucose.
D. protein.
E. starch.
Answer:
Lipid tests
Sudan III is a red fat-soluble dye that is utilized in the identification of the presence of lipids, triglycerides and lipoproteins. The Reaction: Sudan III reacts with the lipids or triglycerides to stain red in colour.
Answer:
I think soo fats and oils
What happens in this circuit if one of the light bulbs burns out?
1. The other light bulb will stay on but get dimmer
2. The battery will lose its charge and stop working
3. Both light bulbs will stop glowing
4. The other light bulb will stay on and glow brightly
6 MARKER FOR CHEMISTRY I NEED THIS!!!
Answer:
when you put the marker in the water the water gets into the marker and it will change the solid color to a plain color witch means that the marker will make the water in the cup the color from the marker.
Hope I can help
What is the frequency of a light wave who has a wavelength of 5.5 x 10-14 m v
Answer:5.45×10^21
Explanation:
Use:f=c/λ
Which diagram above has 4 valence electrons?
Answer:
answer A has four valence electrons
Explanation:
The outer shell has 4 electrons, which are considered the valence electrons
⚠️PLS HELP I HAVE ZERO CLUE AND NEED HELP ASAP DUE AT 12 WILL GOVE BRAINLIEST THANK U⚠️
1/4th of a sample of thorium-232 remains.
How long has the sample been decaying?
Answer:
Explain:i need this too ;-;
A decrease in temperature decreases
. The reaction rate will
Answer:
The reaction rate decreases with a decrease in temperature. ... Molecules joined by stronger bonds will have lower reaction rates than will molecules joined by weaker bonds, due to the increased amount of energy required to break the stronger bonds.
How many H2O molecules are in 2 mol
Answer:
A mole of horses would be Avogadro number of horses (a lot actually !). Avogadro number is 6.023 x 10(23). A mole of H (hydrogen) atoms contains 6.023 x 10(23) H atoms. A mole of H2 molecules contains 6.023 x 10(23) H2 molecules or 2 moles of H atoms (since each molecules has 2 atoms).
Explanation:
Answer:
A mole (mol) is the amount of a substance that contains 6.02 × 10 23 representative particles of that substance. The mole is the SI unit for amount of a substance. Just like the dozen and the gross, it is a name that stands for a number. There are therefore 6.02 × 10 23 water molecules in a mole of water molecules.
Explanation:
A hydrocarbon with vapour density
22 contains 36 g of carbon. What is
its molecular formula?
(C = 12, H= 1).
A. C3H4
B. C3H6
C.
C3H8
D. C4H8
E. C4H10
Answer:
the answer is C4H10 I hope I helped
SOMEONE HELP ME PLEASE I’LL GIVE BRAINLY
Answer:
i think that describes cohesion or hydrolysis
Explanation:
Write the formula iron 11 bromide
Answer:
FeBr2
Explanation:
this isn't really an explanation but it's helpful so here, iron(II) bromide is an inorganic compound with the chemical formula FeBr₂. The anhydrous compound is a yellow or brownish-colored paramagnetic solid. Several hydrates of FeBr₂ are also known, all being pale colored solids.
which example is a weak base?
ethyl alcohol, ammonia, potassium hydroxide or vinegar?
Answer:
potassium
Explanation:
b/c electronegativitu
A layer of sandstone is found on top of a layer of shale
Answer: Yes it is
Explanation:
What is the balanced form of the equation C2H6 + O2→CO2+H2O?
- 2C2H6 + 7O2→4CO2+6H2O
- C2H6 + O2→CO2+2H2O
- C2H6 + 3O2→2CO2+3H2O
- C2H6 + 5O2→3CO2+5H2O
Answer:
- 2C2H6 + 7O2→4CO2+6H2O
Explanation:
Answer:
2C2H6+7O2-->4CO2+6H2O
Hope this helps!
PLZ FASTLEY ANSWER The images show two metamorphic rock samples.
Left: light colored rock with coarse texture. Right: red and white rock with rounded grains and coarse texture.
Which statement accurately describes these rocks?
Both rocks are non-foliated.
Neither rock has randomly arranged grains.
Both rocks formed at Earth’s surface.
Neither rock formed through extreme heat or pressure.
Answer:
a
Explanation:
From the given images, it is clear that both rocks are non-foliated rocks because they don't have distinct repetitive layers. Hence option a is correct.
What are metamorphic rocks?Metamorphic rocks are formed through intense pressure and heating from the sedimentary or igneous rocks. Sometime the change n heat or pressure make the metamorphic rocks gets foliated.
Foliation occurs when pressure forces flat or elongate minerals within a rock to align. These rocks form a platy or sheet-like structure that reflects the pressure direction. There is no platy or sheet-like structure in non-foliated metamorphic rocks.
Non-foliated rocks can be created in a variety of ways. Some rocks, like limestone, are composed of minerals that are not flat or elongate. Therefore, the given rocks are non-foliated.
To find more on foliated rocks, refer here:
https://brainly.com/question/1984747
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A scientist thinks he found a new metal, so he published a paper about this metal. About 1 week after the scientist published the paper, you noticed a problem with the paper the scientist wrote. You noticed that this metal was not a new metal. In fact, this metal was discovered years ago. You determined this when you saw the atomic emission spectrum. As you read the article, you remembered that each atomic emission spectrum is unique to each element and the atomic emission spectrum matched one that was already discovered. Using the techniques from Chemistry, you ran a Flame Test with a piece of the metal (the metal is safe to use) that you had shipped to you. You found the metal turned the flame yellow. What metal did you have in your possession?
**ANSWER CHOICES**
*Barium
*Calcium
*Strontium
*Copper
*Sodium
Answer:
Sodium
because it burns with a yellow-orange flame.
Explanation:
It relates with Barium which burns with yellowish green flame
___ ___ ___ ___ ___ P ___ ___ ___ ___ ___ ___ ___ mediums allow light to pass through
Answer:
I thought the answer was " T R A N S P A R E N T " but I don't know what the extra two letters are! I'm sorry, that's all I've got..
A molecule contains 24.36 g of nitrogen and 62.64g of sliver
Answer:
This molecule is AgN3
Explanation:
Answer:
AgN3
Explanation:
Mass of nitrogen N is given as 24.36 g
Molar mass of nitrogen N= 14 g/mol.
amount of substance in mol of N = mass/molar mass
=24.36 g/ 14 g/mol.
=1.74 mol.
Given mass of silver= 62,64 g.
Molar mass of silver Ag=107.87 g/mol
Number of mols=62.64 g ÷ 107.87 g/mol.
=0.58 mol.
Ratio of number of mol of N and number of mols of Ag = 1.74 mol / 0.58 mol
=3:1
Hence, empirical formula is AgN₃.