Answer:
-9+6-(-2)
-9+6+2
-9+8
-1 is the answer
Explanation:
Why is ice less dense than water?
Answer:
Ice has a very different structure than liquid water
Explanation:
the lattice arrangement allows water molecules to be more spread out than in a liquid, and, thus, ice is less dense than water.
Answer:
Ice has a different structure than water, they align themselves in a regular lattice rather than completely random in a liquid. The orientation of hydrogen bonds cause molecules to push farther apart, which lowers the density.
What would be the concentration of a solution that has 10. g of NaCl and
90. g of water?
Answer:
10%
Explanation:
I think you are looking for mass percent concentration so...
concentration = (mass of solute / total mass of solution) x 100
concentration = (10g of NaCl / (10g of NaCl + 90g of H2O) solution) x 100
concentration = 0.1 x 100
concentration = 10%
Answer:
Concentration of solution is 0.1.
Explanation:
Given data:
Mass of NaCl = 10 g
Mass of water = 90 g
Concentration of solution = ?
Solution:
Formula:
Concentration = mass of solute / total mass of solution
Now we will calculate the total mass of solution:
Total mass of solution = mass of solute + mass of solvent
Total mass of solute = 10 g + 90 g
Total mass of solute = 100 g
Now we will determine the concentration,
C = 10 g/100 g
C = 0.1
Which is an example of a chemical change?
Water evaporating from a puddle
Cloth tearing when pulled
Wood formed sawdust when cut
Bread baking in an oven
Answer:
Its bread My guy. Maholo my dudes.
Explanation:
Which of the following phrases describe the function of the digestive system? Select the two best answers.
I. Smooth, muscular tube connects the mouth to the stomach
II. Muscular action in the esophagus pushes food to the stomach
III. Structures called microvilli increase the surface area of the intestines
IV. Nutrients are made available to the body’s cells
Answer:
Options I & II
I. Smooth, muscular tube connects the mouth to the stomach
II. Muscular action in the esophagus pushes food to the stomach
Explanation:
In digestive systems, we have what we call esophagus. The process is that;
The esophagus we have is a tubular like organ which connects the mouth to the stomach. Now, when we chew food and it's soft, the food will pass through the esophagus after we have swallowed it.
The smooth muscles of the esophagus will now undergo peristalsis which is a series of wave like movements that will push the food toward the stomach.
Thus, we have seen that the esophagus is a smooth tube and that muscle action on it enables the food to be pushed down the stomach.
Thus, options I & II are correct.
Carbon-11 is a radioactive isotope of carbon. Its half-life is 20 minutes. What amount of the initial mass of 70.0g of C-11 atoms in a sample will be left after 80 minutes?
a)5.68 g
b)4.38 g
c)4.20 g
d)3.96 g
e)50.00 g
Answer:
Option B. 4.38 g
Explanation:
The following data were obtained from the question:
Half life (t½) = 20 mins
Original amount (N₀) = 70 g
Time (t) = 80 mins
Amount remaining (N) =.?
Next, we shall determine the decay constant. This can be obtained as illustrated below:
Half life (t½) = 20 mins
Decay constant (K) =.?
Decay constant (K) = 0.693/ half life (t½)
K = 0.693/20
K = 0.03465 min¯¹
Finally, we shall determine the amount remaining after 80 mins as follow:
Original amount (N₀) = 70 g
Time (t) = 80 mins
Decay constant (K) = 0.03465 min¯¹
Amount remaining (N) =.?
Log (N₀/N) = kt/2.303
Log (70/N) = (0.03465 × 80)/2.303
Log (70/N) = 2.772/2.303
Log (70/N) = 1.2036
Take the anti log of 1.2036
70/N = antilog (1.2036)
70/N = 15.98
Cross multiply
70 = N × 15.98
Divide both side by 15.98
N = 70/15.98
N = 4.38 g
Therefore, the amount of the isotope remaining after 80 mins is 4.38 g
William Astbury discovered that the X‑ray diffraction pattern of wool shows a repeating structural unit of approximately 5.2 Å along the length of the wool fiber. Choose the statement that explains the observed 5.2 Å length of the repeating structural unit in the wool polypeptide, α‑keratin.
a. The wool polypeptide α‑keratin exists primarily as a B‑form double helix, where the length of each complete turn of the helix is 5.2 Å.
b. The wool polypeptide α‑keratin consists primarily of α‑helices arranged as coiled coils, where the length of each complete turn of the helix is 5.2 Å.
c. The wool polypeptide α‑keratin has a fully extended backbone and does not contain any regular secondary structure elements.
d. The wool polypeptide α‑keratin consists of left‑handed helices arranged in a triple‑helix coiled coil. In left‑handed helices, the length each complete turn of the helix is 5.2 Å.
Answer:
A
Explanation:
That answer is the only one that makes sense, because according to the law of pulindu, najah is polypeptide akeratin primarly b orm as
Increasing the concentration of substances in a chemical reaction will _____.
Answer:
it will increase the rate of reaction
Answer:
Option (a) is the correct answer.
Explanation:
When we increase the concentration of substances in a chemical reaction then it means there are more number of molecules present in a reaction.
Hence, when these molecules will interact with each other then there will occur more number of collisions. As a result, kinetic energy of molecules will increase and this leads to increase in rate of chemical reaction.
Thus, we can conclude that increasing the concentration of substances in a chemical reaction will increase reaction rate.
Hope this helps!
Have a great day! :))))
From the statements below identify all the chemical changes
Answer:
um... there are no statements below
Explanation:
I can't really help without any statements.
Predict how the milk digestion is affected in individuals that lack functional copies of the gene encoding lactase. Justify your response.
Answer:
Such individuals will be unable to digest milk.
Explanation:
Milk is a substance that contains a disaccharide sugar called LACTOSE. Lactose is a disaccharide sugar composed of glucose and galactose monomers. In order to digest the lactose sugar present in milk, an enzyme called LACTASE is needed.
Since lactase, like every other enzyme, is a protein, it is coded for by a functional gene. However, in an individual that lack functional copies of the gene encoding this lactase enzyme (protein), such individual will be unable to synthesize lactase, hence, be unable to breakdown (digest) lactose sugar in milk.
No lactase gene -> No lactase protein -> No enzyme -> No milk digestion
The grassland have experience a long season of drought which group of organisms would be affected first A decomposer B herbivores C omnivorous D carnivores
Answer:
Herbivores?
Explanation:
The answer is Herbivores because plants are their main source of food and diet. They would be affected first throughout the drought.
(I hope this is a good answer, it is my first time answering a question. I will change this if it is wrong!)
What does the prefix centi mean?
Answer: one hundredth
Explanation:
What is the mass in grams of 2.33 x 1020 atoms of Na?
answer and explnation on the picture if you have any quation let me know
ild a model of ethane, CH_3CH_3CH 3 CH 3 . Looking at one of the carbon atoms, what geometry is present?
Answer:
Each carbon atom is tetrahedral
Explanation:
If we consider a model of ethane, we will quickly discover that all carbon atoms are bonded to four other atoms. This means that there are four regions of electron density around each carbon atom.
According to the valence shell electron pair repulsion theory, when a central atom has four regions of electron density on its outermost shell, the molecule must have a tetrahedral geometry.
why are phase changes horizontal on a heating curve
Answer:
A heating curve graphically represents the phase transitions that a substance undergoes as heat is added to it. The plateaus on the curve mark the phase changes.The second change of phase is boiling, as the temperature stays the same during the transition to gas.
Explanation:
The Length is 4 feet, the width it’s 6 feet and the height is 9 feet. what is the volume
Answer:
216 square feet is the volume
All cells must have energy to function. Most of the energy used by the cells in your body is produced by cellular respiration. In cellular respiration, cells use ____________ to release energy stored in __________.
Answer:
In cellular respiration, cells use oxygen to release energy stored in glucose.
If my answer helped, please mark me as the brainliest!!
Thank You!!
Answer:oxygen and sugars
Explanation:
Matter includes all of the following except
Not everything is matter. Here's a list of what we call NON-MATTER.
___________________________________________________________
Non matter...
LightHeatSound___________________________________________________________
Hope it helps!
May i have brainliest?
[tex]\huge\boxed{Thanks,\;Plip.}[/tex]
How do you find distance please help very fast.
What would you expect to happen if Earth did not tilt on its axis?
Answer:
If the earth did not tilt on its axis we would not have 4 seasons, and it would be hooall the time since when we rotate around the sun the earth with become Hot all the way around.
Explanation:
How many significant figures are in 3.02 x 108 ?
a
2
b 4
C 5
d 3
Answer:
C
Explanation:
the answer has 5 Numbers
Which statement best describes how electrons till orbitals in the penodic table?
Electrons fill orbitals in order of their increasing energy from left to right
o Electrons fill orbitals in order of their increasing energy from right to left
Elements fill orbitals in order of increasing energy from top to bottom in each group
Elements fill orbitals in order of increasing energy from bottom to top in each group.
Answer:
Electrons fill orbitals in order of increasing orbital energy
Explanation:
Apex
The periodic table consists of elements placed in increasing order of atomic numbers. In the table, electrons fill orbitals in increasing orbital energy. Thus, option A is correct.
What is the Aufbau principle?
The Aufbau principle states the filling of the orbitals and subshells of the atom with the electrons based on the energy levels. The electron occupies the lowest energy level.
The filling of the electron proceeds with an increase in the energy levels or the orbitals that in a periodic table increases from left to right across a horizontal row.
In a period, the number of the subshell or orbitals increases with an increase in the atomic number. The electron fills the higher energy levels after they have completely occupied the low energy levels.
Therefore, in option A. the electrons fill from an increasing order of energy levels.
Learn more about the Aufbau principle here:
https://brainly.com/question/15006708
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1. Warm air puts more pressure on Earth than cooler air does.
True
False
Answer:
false I think, but not so sure
The greater the amount of matter that is packed into a given space the greater the
Answer:
density
Explanation:
The liquid-phase reaction follows an elementary rate law and is carried out isothermally in a flow system. The concentrations of the A and B feed streams are 2 M before mixing. The volumetric flow rate of each stream is 5 dm3/min, and the entering temperature is 300 K. The streams are mixed immediately before entering. Two reactors are available. One is a gray, 200.0-dm^3 CSTR that can be heated to 77C or cooled to 0C, and the other is a white, 800.0-dm^3 PFR operated at 300 K that cannot be heated or cooled but can be painted red or black. Note that k = 0.07 dm^3 /mol/min at 300K and E =20 kcal/mol.
Required:
a. Which reactor and what conditions do you recommend? Explain the reason for your choice.
b. How long would it take to achieve 90% conversion in a 200-dm^3 batch reactor with after mixing at a temperature of 77C?
c. What would your answer to part (b) be if the reactor were cooled to 0C?
e kajajdjae no squo viboes we eso doadks Answer:ipao han meExplanation:no
It takes 12.35 grams of acetic acid (CH3COOH; molar mass of 60.05 g/mol) to prepare a
1.5 M solution. What is the volume in L?
Answer:
[tex]V=0.137L[/tex]
Explanation:
Hello.
In this case, since the molarity is computed in terms of the moles of solute (acetic acid) and the volume of the solution in liters, we must first compute the moles of acetic acid by using its molar mass to subsequently compute the volume as follows:
[tex]n=12.35g*\frac{1mol}{60.05g}=0.2057mol[/tex]
[tex]M=\frac{n}{V}\\ \\V=\frac{n}{V}=\frac{0.2057mol}{1.5mol/L}\\ \\V=0.137L[/tex]
Best regards.
A liquid is found to have a volume of 50ml in a graduated cylinder. When placed on a balance, the liquid and graduated cylinder has a mass of 125 g. The empty graduated cylinder has a mass of 75g. What is the density of the liquid?
Answer:
1 g/mL
Explanation:
Density is mass divided by volume ( g/mL)
Find the mass of the water by subtracting 125g - 75g = 50g.
Then divide the mass of the water by the volume of the water: 50g/50mL = 1g/mL
Which has greater internal energy, 1 kg of water or 1 g of water, at the same temperature?
1kg of water has greater internal energy compared to 1g of water because 1kg of water has more mass.
An object will float when:
Answer:
Objects with tightly packed molecules are more dense than those where the molecules are spread out
Explanation:
Answer:
it will float when
Explanation:
there is oxygen present of when the object is not dense
How is Earth's surface most likely to change in a cold place that experiences rainfall?
A- Soil will loosen due to extensive network of tunnels.
B- Rock will break due to repeated abrasion and stress.
C- Mounds of sand will form due to deposition of sediments.
D- Cracks will appear in rocks due to freezing and thawing.
HURRRYYY!!!
Answer:
I think the answer would have to be D
Answer:
I believe it is C
Explanation:
If I am wrong give me 1 star
Why does hard water taste better than distilled water?
Answer:
because hard water is salty