A mystery element has 18 protons. Which one of the following statements is true about the element?
a.The element belongs in row 2 of the periodic table and is classified as a halogen.
b.The element belongs in row 3 of the periodic table and is classified as a noble gas.
c.The element belongs in row 4 of the periodic table and is classified as an alkali metal.
d.The element belongs in row 5 of the periodic table and is classified as an alkaline earth metal.
Answer:
its aragon , so letter b is right
Explanation:
Graphite conducts heat in a similar way to metals because it contains __________ __________. What two words complete the sentence?
Answer:
Free electrons
Explanation:
Graphite conducts heat in a similar way to metals because it contains free electrons.
Conductivity is arised from the delocalization of free electrons. Metals are electron rich and conduct thermally and electrically. Graphite conducts heat in a similar way because it contain delocalized electrons.
What is graphite?Graphite is an allotrope of carbon as diamond and fullerenes. Graphite exhibits a layered helical structures in which the carbon atoms are arranged in a hexagonal fashion.
Substances conduct electricity and heat when they are rich in electrons and are mobile to pass through it. Metals are electropositive and they contains extra electrons which can be delocalized between orbitals or energy levels.
This delocalization of electrons results in an a thermal or electrical current in the substance. Carbon is in sp2 hybridisation in graphite. Where, the electrons can transit from one layer to the other in the layered structure.
Therefore, the presence of delocalized electrons make graphite conducting.
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A chemical property is a change in _____.
hardness
density
composition of matter
physical state
Answer:
Composition of matter
if the products of a reaction have higher energy than the reactants, then the reaction...
Answer:
Explanation:If the products of a reaction have higher energy than the reactants, then the reaction...
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Answer:
Lithium has 1 valence electron, Sulfur has 6
A is oxidized, B is reduced
A is reducing agent, B is oxidizing agent
Explanation:
when an atom loses electrons, it is oxidized
when an atom gains electrons, it is reduced (almost think of when you add a negative number to a positive number, the positive number gets smaller or is reduced)
You have been given four substances that are all white
solids at room temperature. List three specific tests that
you could perform to figure out whether they are ionic or
molecular compounds.
Ionic compounds have a high melting point while molecular compounds have a low melting point.
If I have a white solid, this solid may be ionic or molecular. Ionic substances dissolve in water while molecular substances do not dissolve in water. This is the first test.
Secondly, an ionic solid has a high melting point while a molecular solid has a low melting point. Again, ionic substances are crystalline when felt while molecular compounds are non crystalline when felt.
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Answer: the answer should be A the first one
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what are the statement of ethanol
Answer:
Density 0.78945 g/cm3 (at 20 °C)
Melting point −114.14 ± 0.03 °C (−173.45 ± 0.05 °F; 159.01 ± 0.03 K)
Boiling point 78.23 ± 0.09 °C (172.81 ± 0.16 °F; 351.38 ± 0.09 K)
Solubility in water Miscible
Explanation:
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What is an activation energy
Answer:
Defination of Activation energy :- In chemistry and physics, activation energy is the minimum amount of energy that must be provided for compounds to result in a chemical reaction. The activation energy of a reaction is measured in joules per mole, kilojoules per mole or kilocalories per mole. Meaning of Activation energy :- The minimum quantity of energy which the reacting species must possess in order to undergo a specified reaction.Explanation:
Hope this helps you dear ✌️Carry on learning !!Why is knowledge of the activity series crucial in choosing which metal to build things with?
Answer:
activity series is a list of substances ranked in order of relative reactivity.
For example, magnesium metal can displace hydrogen ions from solution. So magnesium is more reactive than hydrogen:
Mg(s) + 2H⁺(aq) → H₂(g) + Mg²⁺(aq)
Zinc metal can also displace hydrogen ions from solution:
Zn(s) + 2H⁺(aq) → H₂(g) + Zn²⁺(aq)
so zinc is also more active than hydrogen.
But magnesium metal can displace zinc ions from solution:
Mg(s) + Zn²⁺(aq) → Zn(s) + Mg²⁺(aq)
so magnesium is more active than zinc.
The activity series including these elements would be Mg > Zn > H.
Chemists have built up a complete activity series in a similar way.
The most active metals are at the top of the table; the least active are at the bottom.
Any metal that is higher in the series will displace a metal that is below it in a
The knowledge of the activity series in choosing which metal to build things with because; it provides a basis for determining which metal ion is able to displace the other upon chemical interaction.
The choice of building material is a very important design consideration.
This is so because careful consideration must be taken while deciding which metal to build things with as the reactivity of metals vary.This variation is carefully quantified by the position of metals on the activity series.
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What is acid rainnnnnn
Answer:
ACID RAIN
Explanation:
duh
A student draws a model of one of the sun's layers. The student draws arrows to represent hot gas moving away from the center of the sun and other arrows to represent cool gas moving toward the center of the sun. Which layer does the model show?
Radiation Zone
Convection Zone
Chromosphere
Inner Core
Answer:
The convection zone :)
I need help with the question below
Answer:
D po
Explanation:
Sana nakatutulong
#Carry on learning
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What is the total number of neutrons in an atom of O-18? a) 18 b) 16 c) 10 d) 8
Answer:
There are 10 neutrons
Explanation:
Because the atomic number is 8 and the isotope number is 18 (which is the collective protons and neutrons), we can do
18-8=10
Answer:
10
Explanation:
8 proton because it is oxygen
10 neutron because 18-8
Explain why the structure of Copper [ 1s², 2s², 2p⁶, 3s², 3p⁶, 3d¹⁰,4s¹] is more stable than [ 1s², 2s², 2p⁶, 3s, 3p²⁶, 3d⁹,4s² ].
A subshell which is 100% full or 50% full is more stable than subshells which are partially filled with a number of electrons less than or greater than half the number of electrons which can be held by the subshell.
Explanation:
11) When sodium metal is subjected to violet light, it causes the photoelectric effect. However, red light does not affect
the sodium. Explain this phenomena.
The phenomena in which violet light causes photoelectric effect and red light does not is because red light does not achieve the minimum frequency for the phenomenon to occur but violet light does.
The phenomenon in which a substance emits electrons when light is incident upon it is called the photoelectric effect.
This electron would not be emitted if the frequency of the light does not exceed a minimum frequency called the threshold frequency.
Since in the case of the sodium metal, violet light causes the photoelectric effect while red light does not.
This implies that red light does not exceed the minimum frequency for the photoelectric effect to occur, but violet light does thereby causing the photoelectric effect to occur.
So, the phenomena in which violet light causes photoelectric effect and red light does not is because red light does not achieve the minimum frequency for the phenomenon to occur but violet light does.
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a student is given a mixture of sand and salt. describe a method the student could use to separate the mixture.
There is a golden role of solubility, polar solute dissolve in polar solvent and non polar solute dissolve in non polar solvent. Therefore, Salt and sand can be separated by dissolving the salt in water, filtering the mixture, and then evaporating the water to recover the salt.
What is solution?Solutions are a homogeneous mixture of two or more substances. A solution is a homogeneous mixture of solvent and solute molecules. Solvent is a substance that is in large amount in solution.
Solute is the substance which is in small amount in a solution. Salt and sand can be separated by dissolving the salt in water, filtering the mixture, and then evaporating the water to recover the salt.
Therefore, Salt and sand can be separated by dissolving the salt in water, filtering the mixture, and then evaporating the water to recover the salt.
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determine whether each phrase describes starch, glycogen, or cellulose.
Answer:
Starch is a soft, white, tasteless powder that is insoluble in cold water, alcohol, or other solvents.
glycogen is a substance deposited in bodily tissues as a store of carbohydrates. It is a polysaccharide which forms glucose on hydrolysis.
Cellulose is a molecule, consisting of hundreds and sometimes even thousands of carbon, hydrogen and oxygen atoms.
65,000(0.08 x 200x 0.004) / (800x300)
Perform the following operations giving the proper number as a benefit get figures in the answer.
Help
Answer:
Use calculator but first group them one by one and open the bracket by solving them accordingly
The number we get by this operation is 0.016. This number can be taken based on the rules for significant figures.
What is significant figures?The number of significant figures is the number of digits that are known with certainty plus the last one having some uncertainty. All non zero values are significant and zero preceding first non zero digit is not significant .
For example in 65000, there are only two significant figures. Similarly in 0.08 only one significant digit is present. Now when we multiply two decimal numbers, the result can only have as many decimal places as there are in the value with fewest decimal places.
First, multiply the numbers inside the bracket. As per the above rule, the result should contain only two decimal places.
(0.08 ×200×0.004) = 0.06
Multiply by 65000 - 0.06×65000 = 3900
Now divide it by the multiplication product (800× 300), 240000 we get as follows:
3900÷240000 = 0.016
Hence the result of this operation is 0.016.
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Element X is in group 2, and element Y is in group 7, of the periodic table. which ions will be present in the compound formed when X and Y react together?
A) X^+ and Y^-
B)X^2+ and Y^-
C)X^+ and Y^2-
D)X^2- and Y^+
Answer:
Element X has valency 2 while Y Valency 2, element Y has high tendency of gaining electrons for its stability thus the compound formed will be B
elements X is positively charged while Y will be negatively charged
The groups or the families in the periodic table are denoted by the vertical column. Element in group 2 and 7 forms compound with ions X²⁺ and Y⁻. Thus, option B is correct.
What is the periodic group?A group of the periodic table is also called a family that has the elements placed togther with the same number of the valence electron. Group II has two valence electrons and VII has seven valence electrons in the outer shells.
The two valence electrons of the atom can be donated easily compared to acquiring the six electrons to complete the octet and stability. Similarly, the seven valence electrons are hard to donate but can accept one electron to achieve satbility.
The group II element X will donate its two electrons to acquire a +2 charge, whereas group VII element Y will accept one electron and acquire a -1 charge.
Therefore, option B. X²⁺ and Y⁻ presents the ions of the compound.
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Though hydrochloric acid is formed inside our body, it is not called organic acid. Why?
Explanation:
Hydrochloric acid does not consider as organic acid because of the absence of carbon in it.
hope it helps
which of the following are physical properties of nonmentals
You did not provide any options.
What is the mass of 1.20 × 1023 atoms of phosphorus?
show your work, please.
1227.6
Explanation:
po ang sagot khit i calculate nyo
please help me I need it now
Answer:
Ok for the question you can make up your own
If you can't make up your own tell me so I can try my best to come up with questions
1. Answer: Since and last are adverbs so am not sure how that part going to go
Type of Adverb for since is: Time
Type of Adverb for last is : Time
2. Question:
Answer: happily
Type: Manner
Hopes this helps you.
Copper 11 oxide and charcoal are black solids . How would you distinguish between the two solids
What makes inertia important in that activity?
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3. both covalent and ionic
EXPLANATION
Sodium Phosphate is an ionic compound formed by two ions, Sodium Na+ and Phosphate PO−3 . In order for these two polyatomic ions to bond the charges must be equal and opposite. Therefore, it will take three +1 sodium ions to balance the one -3 phosphate ion. However, polyatomic ions are held together by covalent bonds, so this compound contains both ionic and covalent bonds.
A chemist measured the temperature of a liquid to be 26 ∘C, then she heated the liquid to 83 ∘C. By how many Kelvins did the temperature change.
Answer: 57.C
Explanation: simple subtraction
A GIRL WAIKS 10M NORTH,15M EAST AND THEN FINALLY 20MSOUTH FIND HER DISPLACEMENT
Answer:
see this
Explanation: