Answer:
Compared to early humans our brains seemed to have increased in size, and part of the cause may be because of things like Climage change, ecology and social competition
Explanation:
Which of the following represents a 1.00 M (M = mol/dm3) aqueous solution of glucose (C6H12O6)?
A. 180 g glucose per 1000 cm3 solution
B. 10.0 g glucose per 10.0 cm3 water
C. 90.0 g glucose per 500 cm3 water
D. 0.100 g glucose per cm3 solution
In the reaction:
CO3²- + H+ --> HCO³-
The CO3²- ion is considered a base because it
1) accepts a proton
2) accepts an electron
3) donates a proton
4) donates an electron
Thanks! :)
Answer:
1) accepts a proton
Explanation:
CO₃⁻² is a base here because it is accepting a proton ( H⁺) through coordinate bonding by donating a pair of electron .
So option (1) is correct .
l Active transport
IL Simple diffusion
lll Facilitated diffusion
IV. Osmosis
Which of the above type of transport moves molecules against a concentration gradient?
Your answer:
ll and lV only
l only
ll only
Answer:
l only
Explanation:
The movement of substances in living cells can either require energy (active) or not (passive) depending on the direction of movement across concentration gradient. Naturally, substances tend to move down a concentration gradient i.e. difference in concentration, which is from a region of high concentration of water to a region of low concentration. This is the passive type of transport, which does not require energy input. Examples are osmosis, simple diffusion and facilitated diffusion.
However, another type of transport exists in which substances move against the concentration gradient i.e. from a less concentrated region to a more concentrated region. In this case, energy input in form of ATP is required for this kind of transport to occur. This transport is referred to as ACTIVE TRANSPORT. Hence, the answer is I only.
Which of these is an example of interactions between the atmosphere and hydrosphere? (3 points) formation of snow cracking of rocks due to heat destruction of houses by wind uprooting of trees during tornadoes
Answer:
A. formation of snow
Explanation:
The formation of snow is an example of interactions between the atmosphere and hydrosphere.
As snow formation takes place when water vapor converted into liquid through condensation in the clouds. As water droplets rises high in clouds, cooler air present in atmosphere allow to lower the temperature and water droplets form ice or snow.
Hence, the correct option is A.
Answer:
A:formation of snow
Explanation:
these are easily extracted with a pH solution of greater than 7? which one
A) acid drugs
B) metabolites
C) base drugs
D) derivatives
Answer:
base drugs
Explanation:
The pH scale is a scale graduated from 0-14. It is used as an indicator of the degree of acidity or alkalinity. A pH of 0-6.9 indicates acidity. A pH of 7 indicates that the solution is neutral. A solution of pH above 7 indicates that the substance is basic.
It is thus a correct statement to say that any substance that dissolves in solution to produce a solution of pH greater than 7.0 is a basic substance.
If we look at the options closely, it is only a basic drug that will dissolve in water to yield a basic solution of pH greater than 7.0 hence the answer.
Calculating [H.]
DETERMINE THE CONCENTRATION OF HOF EACH SOLUTION
» [OH-] = 1 x 10-IM
CH'] =
» pH = 2
[H] =
» [OH ) = 1 x 10-8 M
(H"]=
» POH= 9
[H] -
Answer:
The answer to your question is given below below:
Explanation:
1. Data obtained from the question:
Concentration of Hydroxide ion, [OH-] = 1x10^-1 M
Concentration of Hydrogen ion, [H+] =..?
The concentration of Hydrogen ion and hydroxide ion are related with the following formula:
[H+] x [OH-] = 1x10^-14
[H+] x 1x10^-1 = 1x10^-14
Divide both side by 1x10^-1
[H+] = 1x10^-14 / 1x10^-1
[H+] = 1x10^-13M
2. Data obtained from the question include:
pH = 2
Hydrogen ion concentration, [H+] =..?
pH = - log [H+]
2 = - log [H+]
-2 = log [H+]
[H+] = antilog (-2)
[H+] = 0.01M
3. Data obtained from the question:
Concentration of Hydroxide ion, [OH-] = 1x10^-8 M
Concentration of Hydrogen ion, [H+] =..?
The concentration of Hydrogen ion and hydroxide ion are related with the following formula:
[H+] x [OH-] = 1x10^-14
[H+] x 1x10^-8 = 1x10^-14
Divide both side by 1x10^-8
[H+] = 1x10^-14 / 1x10^-8
[H+] = 1x10^-6M
4. Data obtained from the question include:
pOH = 9
Hydrogen ion concentration, [H+] =..?
First we shall determine the pH.
The pH and pOH are related with the following formula:
pH + pOH = 14
pH + 9 = 14
Collect like terms
pH = 14 - 9
pH = 5
Now, we can obtain the [H+] as follow:
pH = - log [H+]
pH = 5
5 = - log [H+]
-5 = log [H+]
[H+] = antilog (-5)
[H+] = 1x10^-5M
Compounds formed from only non-metals consist of particles called
Answer:
Compounds formed from non-metals consist of molecules.
Explanation:
The atoms in a molecule are joined together by covalent bonds. These bonds form when atoms share pairs of electrons.
I hope I helped, please correct me if I'm wrong!
Considering the definition of covalent bond and molecules, compounds formed from only non-metals consist of particles called molecules.
But you have to know that the covalent bond is the chemical bond between atoms where electrons are shared, forming a molecule.
Covalent bonds are established between non-metallic elements, such as hydrogen H, oxygen O and chlorine Cl. These elements have many electrons in their outermost level (valence electrons) and have a tendency to gain electrons to acquire the stability of the electronic structure of noble gas.
The shared electron pair is common to the two atoms and holds them together.
In other words, a covalent bond is a type of chemical bond where two atoms of non-metallic elements join to form a molecule, where the atoms share pairs of electrons from their most superficial layer or valence layer to achieve stability in the molecule and thus complying with the octet rule.
In summary, compounds formed from only non-metals consist of particles called molecules.
Learn more:
https://brainly.com/question/12661797?referrer=searchResultshttps://brainly.com/question/4461443?referrer=searchResultshttps://brainly.com/question/11693996?referrer=searchResultsA substance that is made up of more than one atom is called _____.
Answer:
It is called a compound.
Explanation:
Baking soda, NaHCO3, can be commercially produced during a series of chemical reactions called the Solvay process. In this process, NH3(aq), NaCl(aq), and
other chemicals are used to produce NaHCO3(s) and NH Cl(aq).
To reduce production costs, NH3(aq) is recovered from NHCl(aq) through a different series of reactions. This series of reactions can be summarized by the
overall reaction represented by the unbalanced equation below.
NHACH(aq) + Ca(s) - NH3(aq) + H20() + CaCl(aq)
Balance the equation below for the overall reaction used to recover NH3(aq), using the smallest whole-number coefficients.
Answer:
CaO(s) + 2NH4Cl(aq) -------> CaCl2(aq) + H2O(l) + 2NH3(g)
Explanation:
The solvay process is an important process in the chemical industry. In this process, ammonia gas is first dissolved in concentrated brine to form a mixture known as ammoniacal brine. This solution is made to trickle down the tower. A counter stream of carbon dioxide is forced up the tower. The two substances react to form sodium hydrogen trioxocarbonate IV. This substance is only slightly soluble and separates out as a solid sludge. The product is now dried and heated to give sodium trioxocarbonate IV.
The overall reaction of the process can be given as;
CaO(s) + 2NH4Cl(aq) -------> CaCl2(aq) + H2O(l) + 2NH3(g)
Calcium chloride is merely a by-product.
Answer:
Based on Reference Table F, which solution will contain the highest concentration of
iodide ions?
A
lead iodide
silver iodide
mercury (II) iodide
iron (11) iodide
A student dissolves 1 g of sugar in 10 g of water she then determines the mass of the solution what is the mass of dissolved sugar and water
Answer:
11grams
Explanation:
Use the law '' conversation of mass ''
Because the sugar dissolved in water.
Cheers! :D
PS: Mark me as brianest. Thx.
Why does common table salt (NaCl) have a high melting point?
A.
It forms an ionic bond with a crystal lattice structure.
B.
It forms a covalent bond with a Lewis dot structure.
C.
It forms a metallic bond with an electron sea model structure.
D.
It forms a covalent bond by sharing electrons.
E.
It forms a metallic bond with a Lewis dot structure.
Answer:C is not the answer. I just got it wrong in Edmentum
Explanation:
What is pressure?
O A. The heat required to change the temperature of a gas
OB. The force of gas molecules hitting their container
O C. The mixing of gas molecules due to random motion
D. The space occupied by gas molecules moving around
Answer:
B.
Explanation:
The force of gas molecules hitting their container is pressure.
Because pressure = force/area.
10 Points
Atoms are very small. Approximately how many atoms would it take to
make a stack as thick as a potato chip?
O
A. Thousands
O
B. Hundreds
C. Billions
OD. Millions
Reset Selection
Answer:
C. Billions
Explanation:
or even more
what are two factors about particles that enable them to form solutions (SCIENCE)
Answer:
temperature and whether or not they are polar or non-polar.
Why is rusted iron an example of an oxidation reduction reaction A. Electrons are exchanged B. Heat is generated C. Iron combines with oxygen D. Iron becomes molten E. Oxygen is used
Answer:
C
Explanation:
Oxygen & water form rust
how does photosynthesis and respiration in plants influence the amount of co2 in the atmosphere during a year?
Answer:
An increase in the amount of CO2 well increase the rate of photosynthesis, Carbon dioxide concentration will directly affect the rate of photosynthesis as it is used in the photosynthesis reaction.Increased amount of CO2 will increase the rate of photosynthesis to a certain limit, after which a further increase in its amount will no longer increase the rate any further.
Hope this helps.
Cheers! :)
Choose the correct coefficients to balance the following equation: __CaCO3 + __HC; Produces __CaCl2 + __CO2 + __H2O
Answer:
CaCO3 + 2HCl = CaCl2 + CO2 + H2O
Explanation:
CaCO3 + HCl = CaCl2 + CO2 + H2O
Error in equation should be HCl on left hand side not HC
Left Side
Ca = 1
C = 1
O = 3
H = 1
Cl = 1
Right Side
Ca = 1
C = 1
O = 3
H = 2
Cl = 2
So we'll try and balance the Chlorine
CaCO3 + 2HCl = CaCl2 + CO2 + H2O
Left Side
Ca = 1
C = 1
O = 3
H = 2
Cl = 2
Right Side
Ca = 1
C = 1
O = 3
H = 2
Cl = 2
Yay it worked
A 39 foot ladder is resting against a wall that is 36 feet high. What is
the distance between the base of the ladder and the bottom of the wall?
5 feet?
15 feet?
10 feet ?
calculate the amount of I - 125 that remains after 178.2 days if we started with 300 grams.
Answer:
38.3 g
Explanation:
The half life of a substance is the time taken for the substance to decay to about half of its amount.
Let us assume that I-125 have a half life of 60 days. It means that every 60 days, the amount of I - 125 would be halved.
The amount of I - 125 (A) that remains after t days is given by:
[tex]A=A_o*\frac{1}{2^n} \\[/tex]
Where Ao is the initial amount and n = t / half life
Given that:
Ao = 300 g, t = 178.2 days.
Therefore n = t / half life = 178.2 days / 60 days = 2.97
[tex]A=A_o*\frac{1}{2^n} \\A=300*\frac{1}{2^{2.97}}\\ A=38.3\ g[/tex]
The use of nuclear energy can have both positive and negative consequences. Which of the following is a positive consequence of using nuclear energy? a. Nuclear energy uses nonrenewable resources. b. Nuclear energy produces little air pollution. c. Uranium ore used for nuclear power plants must be mined and processed. d. Nuclear energy has no environmental impact. Please select the best answer from the choices provided A B C D
Answer
its B
Explanation:
B.
Nuclear energy produces little air pollution.
How many grams of aluminum oxide would be produced from the reaction of 0.25 grams of aluminum with excess oxygen gas?
Answer:
0.472 grams of aluminum oxide would be produced from the reaction of 0.25 grams of aluminum with excess oxygen gas.
Explanation:
First of all, you should know that the balanced reaction that occurs:
4 Al + 3 O₂ → 2 Al₂O₃
Then, by stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts are produced in moles:
Al: 4 molesO₂: 3 molesAl₂O₃: 2 molesBeing:
Al: 27 g/moleO: 16 g/moleThe molar mass of the compounds participating in the reaction is:
Al: 27 g/moleO₂: 2*16 g/mole= 32 g/moleAl₂O₃: 2*27 g/mole + 3*16 g/mole= 102 g/moleThen, by stoichiometry of the reaction, the following amounts of mass react and are produced:
Al: 4 moles*27 g/mole= 108 gO₂: 3 moles*32 g/mole= 96 gAl₂O₃: 2 moles*102 g/mole= 204 g
Now it is possible to apply the following rule of three: if 108 grams of Al produce 204 grams of Al₂O₃, 0.25 grams of aluminum how much mass of Al₂O₃ will it produce?
[tex]mass of Al_{2} O_{3} =\frac{0.25 grams of Al*204 grams of Al_{2} O_{3} }{108 grams of Al}[/tex]
mass of Al₂O₃=0.472 grams
0.472 grams of aluminum oxide would be produced from the reaction of 0.25 grams of aluminum with excess oxygen gas.
Answer:
D
Explanation:
I know the correct answer is either a or d. Can anyone explain which one it is and why? CH3C ≡ CCH2CH2Cl is named: a. 1-chloro-3-pentyne b. 5-chloro-2-pentene c. 1-acetylenyl-3-chloropropane d. 5-chloro-2-pentyne
Answer:
D.
Explanation:
CH₃C≡ CCH₂CH₂Cl
Since there are 5 carbons so the suffix used is "pent"
There is a triple bond so its alkyne
So the compound becomes 2-pentyne (2 because the triple bond is with the 2nd carbon)
Then,
The functional group of chlorine is attached with 5th carbon So the compound becomes
5-chloro,2-pentyne
A moving train comes to a stop at the station. What happened to
make the train change motion?
1)The train experienced an unbalanced force.
2)The train experienced a balanced force.
3)The train would stop with or without forces.
4)The train does not experience forces acting on it.
Which statement describes a periodic trend of first ionization energy?
O A. It tends to decrease from left to right across a period.
B. It remains the same within a period.
O C. It tends to increase from top to bottom of a group.
D. It tends to decrease from top to bottom of a group.
Answer:
D
Explanation:
when ionic radius gets bigger, the valence electron is repelled further away from the nucleus due to higher number of principal quantum shells. it experiences less electrostatic forces of attraction with the nucleus and requires less energy to remove.
how many moles of hydrogen will react with 40g oxygen
Answer: 2.5 moles
2H2 + O2 = 2H2O
This implies that 2 moles of oxygen is needed to react with one mole of oxygen to form 2 moles of water
It also implies that
2 moles of hydrogen requires 32 grams of oxygen
? moles of hydrogen would require 40 g of oxygen
2 x 40/32 = 2.5 moles
Which type of crystal is typified by a sea of delocalized electrons
surrounding the lattice?
O A. lonic
B. Metallic
OC. Macromolecular
D. Chemical
Reset Selection
B.metallic is the answer hope this helped
The correct answer is option B. Metallic.
What explains the structure of metals and delocalized electrons?
Metal is composed of a huge structure of atoms arranged in a regular pattern. Electrons from the outer shell of a metal atom are delocalized and can move freely throughout the structure. This sharing of delocalized electrons results in strong metal bonds.
Metallic bonds are electrostatic attraction between metal cations and the negatively charged ocean of delocalized electrons. The sea of delocalized electrons contains only valence electrons, not core electrons.
Learn more about Metal here: https://brainly.com/question/4701542
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If they are traveling at the same speed, which will have the most kinetic energy?
A. A 5-kilogram ball
B. A 25-kilogram ball
C. A 10-kilogram ball
D. A 1-kilogram ball
Answer: B. (A 25 kg ball)
Explanation:
Since [tex]KE = \frac{1}{2} mv^{2} \\[/tex], and velocity is the same for all four balls, the ball with the greatest mass will have the greatest kinetic energy (since mass and KE are directly related). Below shows these calculations:
A. m = 5
[tex]KE = \frac{1}{2} mv^{2} \\[/tex]
[tex]KE = \frac{1}{2} (5)v^{2} \\[/tex]
[tex]KE = 2.5v^{2} \\[/tex]
B. m = 25
[tex]KE = \frac{1}{2} mv^{2} \\[/tex]
[tex]KE = \frac{1}{2} (25)v^{2} \\[/tex]
[tex]KE = 12.5v^{2} \\[/tex]
C. m = 10
[tex]KE = \frac{1}{2} mv^{2} \\[/tex]
[tex]KE = \frac{1}{2} (10)v^{2} \\[/tex]
[tex]KE = 5v^{2} \\[/tex]
D. m = 1
[tex]KE = \frac{1}{2} mv^{2} \\[/tex]
[tex]KE = \frac{1}{2} (1)v^{2} \\[/tex]
[tex]KE = 0.5v^{2} \\[/tex]
Which of the following always occurs in a
chemical reaction?
A) a gas is given off.
B) a solid is produced,
C) a new substance is produced.
D) a colour change takes place.
Answer:
C
Explanation:All the other answers are wrong
What is the value of log 43? Use the calculator. Round your answer to the nearest tenth.
Answer:
1.6
Explanation:
log 43 = 1.6335
B, 1.6
Explanation: E21
Balance this equation. If a coefficient of "1" is required, choose "blank" for that box.
C + Fe ₂ O ₃ → CO ₂ + Fe
Answer:
3C + 2Fe ₂ O ₃ → 3CO ₂ + 4Fe
Explanation:
C + Fe ₂ O ₃ → CO ₂ + Fe
Left Side
C = 1
Fe = 2
O = 3
Right Side
C = 1
Fe = 1
O = 2
So we can see that while Carbon is balanced Fe and O are not.
We then attempt to balance the equation by balancing the Oxygen.
C + 2Fe ₂ O ₃ → 3CO ₂ + Fe
Left Side
C = 1
Fe = 4
O = 6
Right Side
C = 3
Fe = 1
O = 6
Oxygen is now balanced but C and Fe are not, though this is an easy fix as each are independent on each side of the equation.
3C + 2Fe ₂ O ₃ → 3CO ₂ + 4Fe
Left Side
C = 3
Fe = 4
O = 6
Right Side
C = 3
Fe = 4
O = 6
Answer:
2 , 3 , 4 , 3
Explanation: