Water exists on other planets in the solar system. Life exists only on Earth because water exists as a liquid on Earth.
Why?The boiling point of water is 100 °C and the freezing point is 0 °C. A normal temperature on Earth is 25 °C, meaning that water is generally found in the liquid state on Earth.
Liquid water is essential for life because it is at the same time an essential molecule for photosynthesis (the basis of all energy processes needed for life), and a medium where nutrients and waste circulate in living beings.
Have a nice day!
Which material does not melt at any temperature? wood, a mixture of different substances ethanol, a molecular compound sodium chloride, an ionic compound iron, a metallic element description?
The combining of the nuclei of atoms is known as nuclear _____.
A.) fission
B.) fusion
C.) bombardment
D.) fallout
The average strength of a hydrogen bond is approximately what percent of the average strength of a covalent bond?
a. 50 %
b. 10 %
c. 5 %
d. 100 %
Hydrogen bonds are
approximately 5% of the bond strength of covalent bonds, for example (C-C or C-H
bonds).
Hydrogen bonds strength in water is approximately 20
kJ/mol, strenght of carbon-carbon bond is approximately 350 kJ/mol
and strengh of carbon-hydrogen bond is approximately 340 kJ/mol.
20 kJ/350 kJ = 0,057 = 5,7 %.
Final answer:
The strength of a hydrogen bond is approximately 5% that of a covalent bond. The correct answer is c. 5%.
Explanation:
The average strength of a hydrogen bond is approximately 5% of the average strength of a covalent bond. Therefore, the correct answer to the question is c. 5%. Hydrogen bonds are a type of intermolecular attractive force where a hydrogen atom covalently bonded to an electronegative atom is attracted to a lone pair of electrons on a neighboring molecule. While hydrogen bonds are much stronger than other dipole-dipole interactions, they are still significantly weaker than covalent bonds, but integral for holding together structures like DNA and proteins in biology.
EASY
Elements in the same period have _____.
similar properties
the same number of protons
the same number of electron shells
the same number of electrons
Answer:
THE SAME NUMBER OF PROTONS
Explanation:
Elements in the same period or row will have the same number of electron shells. So the correct option is C.
What are electron shells?
The electron shell of an atom is the region that surrounds the atomic nucleus which contain a particular number of electrons. Each of the electron orbit allowed has been given a quantum number of n.
It can run from 1, which is for the orbit that is closest to the nucleus to infinity, which is for the orbits totally far from the nucleus. All of the orbitals that have the same value of n constitute an electronic shell.
Inside each of the atomic shells, there are also subshells. These correspond to the different rates of rotation and orientation of the orbitals and also to the directions of the spin of the electrons.
Generally, if the shell is far away from the nucleus or the value of n is higher, the number of subshells will also be higher.
Therefore the correct option is C.
Read more about electron shells, here
https://brainly.com/question/491265
#SPJ6
If a hurricane destroyed an entire U.S. city, what category would it most likely be?
A)category 1 or 2
B)category A or B
C)category X or Y
D)category 4 or 5
Please help with chem question
The chemical formula for cesium oxide is Cs2O. What is the charge of cesium? +1 +2 –1 –2
Answer:
The correct answer, the charge of Cesium is +1
Explanation:
Hi!
Let's solve this!
The compound is: Cs2O.
We know that the oxygen valence number is -2.
We also know that the compound has to be balanced, so to balance the charges we need +2. As there are two Cs, we perform the following operation:
2 * (+ 1) -2 = + 2-2 = 0
We conclude that the correct answer, the charge of Cesium is +1
An unknown compound contains only carbon, hydrogen, and oxygen (cxhyoz). combustion of 5.00 g of this compound produced 7.33 g of carbon dioxide and 3.00 g of water. how many moles of carbon, c, were in the original sample?
Answer : The number of moles of carbon in the original sample were 0.166 moles.
Explanation :
The chemical equation for the combustion of hydrocarbon having carbon, hydrogen and oxygen follows:
[tex]C_xH_yO_z+O_2\rightarrow CO_2+H_2O[/tex]
where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.
We are given:
Mass of [tex]CO_2=7.33g[/tex]
Mass of [tex]H_2O=3.00g[/tex]
We know that:
Molar mass of carbon dioxide = 44 g/mol
For calculating the mass of carbon:
In 44 g of carbon dioxide, 12 g of carbon is contained.
So, in 7.33 g of carbon dioxide, [tex]\frac{12}{44}\times 7.33=1.99g[/tex] of carbon will be contained.
Now we have to calculate the moles of carbon.
Moles of Carbon =[tex]\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{1.99g}{12g/mole}=0.166moles[/tex]
Therefore, the number of moles of carbon in the original sample were 0.166 moles.
What is the formula of the compound that contains iron (ii) (fe2+) and sulfate (so42–) ions?
FeSO4 iron sulfate.
what is iron sulfate?Iron(II) sulfate or ferrous sulfate denotes a range of salts with the formula FeSO₄·xH₂O. those compounds exist most typically as the heptahydrate but several values for x are known. The hydrated form is used medically to treat iron deficiency, and additionally for business applications.
what is iron sulfate used for?Ferrous sulfate (or sulfate) is a medicine used to treat and prevent iron deficiency anemia. Iron allows the body to make healthy red blood cells, which deliver oxygen across the body. some matters such as blood loss, pregnancy, or too little iron in your diet could make your iron supply drop too low, leading to anemia
Learn more about ferrous sulfate here
https://brainly.com/question/24636413
#SPJ2
Which statement describes the structure of an atom?
1)The nucleus contains positively charged electrons.
2)The nucleus contains negatively charged protons.
3)The nucleus has a positive charge and is surrounded by negatively charged electrons
4)The nucleus has a negative charge and is surrounded by positively charged electrons
4)
The correct answer is; "The nucleus has a positive charge and is surrounded by negatively charged electrons"
The atom is composed of three particles, electrons, protons and neutrons.
The electrons are negatively charged, protons are positively charged while neutrons have no charge.
The protons and neutrons are housed in the nucleus of the atom. Since the protons are positively charged, the nucleus is regarded as being positively charged.
The nucleus is surrounded by negatively charged electrons.
https://brainly.com/question/14156701
Consider the reaction h2(g) + cl2(g) ⇀↽ 2 hcl(g), which is exothermic as written. what would be the effect on the equilibrium position of increasing the temperature?
Answer:
Backward direction
Explanation:
Exothermic reaction: It is that reaction in which heat is evolved during reaction.
We are given
[tex]H_2+Cl_2\rightleftharpoons 2HCl[/tex]
It is exothermic reaction.
We know that in exothermic reaction when we increase the temperature then the equilibrium shift in backward direction and when we decrease the temperature then the equilibrium shift in forward direction.
Therefore, when we increasing the temperature then the equilibrium shift in backward direction.
A substance is 89.2% carbon by mass. how much of the substance would be needed to recover 34.6 mol of pure carbon?
Answer:
The amount of substance we need to recover 34.6 mol of carbon is 465.47g
Explanation:
we want to know what mass of substance we need to recover 34.6 mol of carbon
This substance is composed of 89.2% carbon
Wmust recover 34.6 mol of carbon and we know that the molecular mass of carbon is 12g / mol this means that one mole of carbon has a mass of 12 g
We use a simple rule of three to know how many grams of carbon are in 34.6 mol
[tex]1 mol C\longrightarrow 12g\\34.6 mol C\longrightarrow x\\x=\frac{(34.6)(12)}{1}= 415.2 g[/tex]
415.2 g are 34.6 mol of carbon
As the amount of carbon we want to recover is 415.2g (34.6mol) and this amount corresponds to 89.2% of the total
To calculate the total mass we need we use a simple rule of three
[tex]89.2\%\longrightarrow 415.2 g\\100\%\longrightarrow x\\x=\frac{(100)(415.2)}{89.2}\\ x= 465.4g[/tex]
The amount of substance we need to recover 34.6 mol of carbon is 465.47g
What is a common way to correct nearsightedness
Nearsightedness or myopia is a condition where the person can see the near objects clearly but distant objects appears blurred. This eye condition is corrected with contact lenses or prescription eyeglasses. Another approach is LASIK or corrective eye surgery. In LASIK laser is used to correct the vision.
A generic gas, x, is placed in a sealed glass jar and decomposes to form gaseous y and solid z. 2x(g)â½ââây(g)+z(s) how are these equilibrium quantities affected by the initial amount of x(g) placed in the container? assume constant temperature.
A chemical bond is classified as a covalent bond if it involves the transfer of electrons.
a. True
b. False
Answer:
true
Explanation:
because i said so
Calculate the molarity of each aqueous solution: (a) 25.5 ml of 6.25 m hcl diluted to 0.500 l with water (b) 8.25 ml of 2.00×10–2 m ki diluted to 12.0 ml with water
Final answer:
To calculate the molarity of diluted aqueous solutions of HCl and KI, we apply the dilution formula M1V1 = M2V2, producing final molarities of 0.319 M for HCl and 1.37×10⁻² M for KI.
Explanation:
The question involves calculating the molarity of two different aqueous solutions after dilution. For both parts (a) and (b), we will apply the concept that molarity (M) is the number of moles of solute per liter of solution, and that the number of moles of solute remains constant during the dilution process, allowing us to use the equation M1V1 = M2V2, where M1 and V1 are the initial molarity and volume, respectively, and M2 and V2 are the final molarity and volume, respectively.
For the solution of HCl: Given an initial volume of 25.5 mL (or 0.0255 L) and molarity of 6.25 M, diluted to a final volume of 0.500 L, the final molarity (M2) can be calculated as follows:M2 = (M1 × V1) / V2 = (6.25 M × 0.0255 L) / 0.500 L = 0.319 M.
For the solution of KI: With an initial volume of 8.25 mL (or 0.00825 L) and molarity of 2.00×10⁻² M, diluted to a final volume of 12.0 mL (or 0.012 L), the final molarity is calculated similarly: M2 = (M1 × V1) / V2 = (2.00×10⁻² M × 0.00825 L) / 0.012 L = 1.37×10⁻² M.
Which of the following is an example of a defined contribution plan?'
a) 401(k)
b) Keogh plan
c) Both a and b
401(k) and Keogh plan both are an example of a defined contribution plan and the correct option is option C.
What is defined contribution plan?A defined contribution (DC) plan is a retirement plan that's typically tax-deferred, like a 401(k) or a 403(b), in which employees contribute a fixed amount or a percentage of their paychecks to an account that is intended to fund their retirements.
In addition, the sponsor company can match a portion of employee contributions as an added benefit.
These plans place restrictions that control when and how each employee can withdraw from these accounts without penalties.
Therefore, 401(k) and Keogh plan both are an example of a defined contribution plan and the correct option is option C.
Learn more about Defined contribution plan, here:
https://brainly.com/question/28603314
#SPJ3
The compound ncl3 is nitrogen trichloride, but alcl3 is simply aluminum chloride. why? check all that apply. check all that apply. the compound alcl3 is an ionic compound (metal and nonmetal), and therefore does not require prefixes\-âso alcl3 is aluminum chloride. ncl3 is a molecular compound (two or more nonmetals), and therefore in its name prefixes indicate the number of each type of atom\-âso ncl3 is nitrogen trichloride. alcl3 is a molecular compound (two or more nonmetals), and therefore in its name prefixes indicate the number of each type of atom\-âso alcl3 is aluminum chloride. the compound ncl3 is an ionic compound (metal and nonmetal), and therefore does not require prefixes\-âso ncl3 is nitrogen trichloride. none of the above.
The compound [tex]AlCl_3[/tex] is an ionic compound (metal and nonmetal) and therefore does not require prefixes so [tex]AlCl_3[/tex] is aluminum chloride.
[tex]NCl_3[/tex] is a molecular compound (two or more nonmetals), and therefore in its name prefixes indicate the number of each type of atom so
[tex]NCl_3[/tex] is nitrogen trichloride.
FURTHER EXPLANATIONBinary Ionic Compound NomenclatureIonic compounds are compounds made up of metals and nonmetals. Metals are elements that readily lose valence electrons and form positively charged ions called cations. Nonmetals are atoms that readily gain electrons and form negatively charged ions called anions.The electrostatic attraction between these oppositely charged ions pulls and holds them together forming the ionic compound.The compound is named based on the name of the cation and anion that it is made of.The cation name is simply the name of the metal element plus the word ion.The anion name is the first or first two syllables of the name of the nonmetal element plus the suffix -ide.Example: KClcation name: potassium ion
anion name: chloride
compound name: potassium chloride
Covalent (Molecular) Compound NomenclatureMolecular compounds are a group of nonmetal elements that are sharing their electrons for stability. They are named by using prefixes that correspond to their subscripts (how many atoms of the element is present in the molecule).The prefixes include:mono - 1 hexa - 6
di - 2 hepta - 7
tri - 3 octa - 8
tetra - 4 nona - 9
penta - 5 deca - 10
The prefix mono- is never written for the first element of a covalent compound but may be used for the second or succeeding elements (e.g. CO is carbon monoxide NOT monocarbon monoxide).Example: [tex]CO_2[/tex]no. of carbon atom = 1 (mono-)
no. of oxygen atom = 2 (di-)
name of the compound: carbon dioxide
LEARN MOREIon Formation brainly.com/question/6177640Chemical Formula https://brainly.com/question/4697698Keywords: nomenclature, ionic, molecular
AlCl3 is an ionic compound, which means that the aluminium cation and chlorine anion make up its structure. Strong electrostatic forces hold the two elements' strong ionic connection together.
Because of this, the compound's name just needs to include the prefix aluminium chloride. However, the substance NCl3 is a molecular molecule, which means that it is made up of two non-metals, namely nitrogen and chlorine.
Prefixes are needed in the name of this element to denote the number of each kind of atom present since the link between these two elements is weaker than the ionic interaction between aluminium and chlorine. Thus, the substance is sometimes referred to as nitrogen trichloride.
Learn more about compound at:
https://brainly.com/question/24972577
#SPJ6
If 33.6 grams of KCl are dissolved in 192 grams of water, what is the concentration of the solution in percent by mass? A. 21.2% KCl B. 5.71% KCl C. 14.9% KCl D.17.5% KCl
How many moles of oxygen would be needed to react with 6 moles of ethane?
The mole of oxygen needed to react with 6 moles of ethane is 1.16 mol.
What are combustion reactions?Combustion reactions are those in which the substance react with oxygen and produce heat and light.
The reaction will be
[tex]\rm 2C_2H_6 + 7O_2 = 4CO_2 + 6H_2O[/tex]
Now,
[tex]1\; mole\;of \;ethane \times \dfrac{7\;mol\;ofO_2}{6\;mol\;of\;C_2H_6} = 1.16 mol[/tex]
Thus, the moles of oxygen is 1.16 mol.
Learn more about combustion, here:
https://brainly.com/question/9641392
Final answer:
To react with 6 moles of ethane, 21 moles of oxygen would be needed.
Explanation:
To determine the number of moles of oxygen needed to react with 6 moles of ethane, we need to use the balanced chemical equation for the reaction. The balanced equation for the combustion of ethane is:
C2H6 + 3.5O2 → 2CO2 + 3H2O
From the balanced equation, we can see that 1 mole of ethane reacts with 3.5 moles of oxygen. Therefore, 6 moles of ethane would require:
(6 moles ethane) * (3.5 moles O2 / 1 mole ethane) = 21 moles of oxygen
Radioactivity in our world _____.
a. is something relatively new
b. is as old as the universe
c. was invented in 1913
d. was caused by atomic bombs
How many moles of co2 are produced when 5.40 mol of ethane are burned in an excess of oxygen?
When 5.40 moles of ethane are burned in excess oxygen, 10.80 moles of carbon dioxide are produced.
The balanced chemical equation for the combustion of ethane (C₂H₆) in oxygen (O₂) is:
C₂H₆ + 7/2 O₂ -> 2 CO₂ + 3 H₂O
From the balanced equation, we can see that 1 mole of ethane (C₂H₆) produces 2 moles of carbon dioxide (CO₂) during combustion. This means that the mole ratio of ethane to carbon dioxide is 1:2.
Given that 5.40 moles of ethane are burned, we can use this mole ratio to calculate the moles of carbon dioxide produced:
5.40 moles of C₂H₆ x (2 moles of CO₂ / 1 mole of C₂H₆) = 10.80 moles of CO₂
So, when 5.40 moles of ethane are burned in excess oxygen, 10.80 moles of carbon dioxide are produced.
To learn more about moles, here
https://brainly.com/question/34302357
#SPJ3
Very unsure on my answers for these 2 questions. I really have no idea what I'm doing. Could someone please explain? Will give medal and maybe become a fan if someone would just help me understand! Please?
1. Which of the following energy yields is likely to have come from a fission or fusion reaction?
1.0 × 10^2 kJ/mol
2.5 × 10^2 kJ/mol
1.2 × 10^3 kJ/mol
*This one??? 1.4 × 10^11 kJ/mol
2. In a nuclear reaction, a change in mass of 1.0 × 104 g occurs. What is the corresponding change in energy? Use the formula E = mc2.
9.0 × 10^3 kJ
*My best guess... 9.0 × 10^6 kJ
9.0 × 10^9 kJ
9.0 × 10^12 k
Balance the equation of 2 c6h12o6 + 6 o2--> __ co2 + __ h2o
In which of the following is the solution concentration expressed in terms of molarity?
A. 10g of solute/ 1000g of solution
B. 10g of solute/ 1000mL of solution
C.10mL of solute/ 1L of solution
D.10 mol of solute/ 1L of solution
Molarity is a concentration unit that is expressed as the number of moles of the solute per liter of solution. Only Option D (10 mol of solute/ 1L of solution) presents the solution concentration in terms of molarity.
Explanation:In chemistry, molarity is a concentration unit that is expressed as the number of moles of the solute per liter of solution. In this context:
Option A represents a weight to weight percent concentration, not molarity.
Option B, though it seems similar to molarity, is not equivalent due to using mass (g) instead of moles for the solute.
Option C would be considered dilution, wherein the volume of a solution is increased, thus decreasing the solute's overall molarity.
Only Option D (10 mol of solite/ 1L of solution) directly aligns with the definition of molarity and represents the solution concentration in terms of molarity.
https://brainly.com/question/31815736
#SPJ6
The electromagnetic that is emitted from radioactive elements is released in the form of _____
Gamma Rays
Beta Particles
Neutrons
Alpha Particles
Which carbon compound is soft, slippery, a decent electricity conductor, and bonded in a way that forms planes?
coal
petroleum
graphite
Answer:
Graphite.
Explanation:
Hello,
Graphite, plumbago or black lead, is a mineral making up of carbon as its main atom. It has an aromatic-like structure that consists of rings of six carbon atoms assembled in widely spaced horizontal planes. It is extremely soft, and slippery, cleaves at low pressure. Moreover has a very low specific gravity making it a decent electricity conductor. In addition, it successfully withstands heat.
Best regards.
Which of the following is an example of symbiosis?
A. A mother bear taking care of her cubs
B. A married couple who split their rent
C. A tick feeding off of its host
D. One chimp cleaning and grooming the hair of another chimp
Answer:
c
Explanation:
im doing it now and the answer above me is wrong
A combination of bonded atoms attached to a carbon skeleton is called
Why is a drip irrigation system more sustainable than traditional spraying methods of irrigating crops?
A. It leads to reduced river flow.
B. It causes the water table to drop.
C. It reduces pollution from runoff.
D. It decreases water quality.
Answer: C
Explanation: Just took the test.