Calculate the volume in mL of a stock solution of 100% ethanol, required to prepare 2 L of a 70% solution of ethanol in dH2O
Answer:
For example, to make 70% ethanol from 95% ethanol, take 70 mL of 95% ethanol and add enough water to bring the volume to 95 mL. You will then have 95 mL of 70% ethanol. This works for any dilution and all that is required is a large enough graduated cylinder.
When using liquid reagents, the percent concentration is based upon volume per volume, i.e. #ml/100ml. Example 2: If one wished to make a 70% ethanol solution, 70 ml of 100% ethanol would be dissolved in 30 ml of water (or the equivalent for whatever volume was needed).
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An oven is a technological system. Which of the following describes an input into this system?
A. setting the temperature
B. Burning gas releases heat.
C. A thermostat monitors the temperature and increases the gas flow when the temperature falls too low.
D. A cake is baked.
Answer:
c got it right on my quiz
Explanation:
What does DNA replication ensure?
Answer:
To ensure that mistakes, or mutations, are not introduced, the cell proofreads the newly synthesized. Once the DNA in a cell is replicated, the cell can divide into two cells, each of which has an identical copy of the original DNA.
Explanation:
do you like this image i found on instagram???
Answer:
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Answer:
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Explanation:
How does water cause frost wedging?
A
Water attracts lightning, which breaks apart huge boulders into many smaller pieces.
B
Water carries sediment to large rocks, causing them to rub against each other.
C
Water freezes and thaws inside rock cracks, causing them to widen and then split.
D
Water slowly wears down a rock’s sharp edges, leaving behind a smooth surface.
Answer:
C. Water freezes and thaws inside rock cracks, causing them to widen and then split.
Explanation:
When water gets in the crack at the bottom and freezes, frost wedging occurs.
Frost wedging happens when water gets in crack, freezes, and expands. This process breaks rocks apart. When this process is repeated, cracks in rocks get bigger and bigger (see diagram below) and may fracture, or break, the rock.
Which of these best describes weathering and erosion?
A
They are tools people use to change landforms and create new ones.
B
They only affect one landform: islands.
C
They cause tiny changes to Earth’s surface that become enormous over time.
D
They significantly change the surface of the Earth every few days.
The best description of weathering and erosion should be considered as the option d. They significantly change the surface of the Earth every few days.
What is weathering and erosion?Weathering represent the break down or the rocks should be dissolved out and the minerals should be on the earth surface.
When the rock should be split down so this process we known as the erosion transports.
Therefore, the option d is correct.
Learn more about earth here: https://brainly.com/question/12004410
Please help 16 points
Answer:
its A
Explanation:
Carbon dioxide + water + energy from light produces glucose and oxygen
Discuss at least 3 ways that animals move.
Answer:
Walk, fly, and swim.
Explanation:
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What is the main negative effect of slash and burn deforestation in rainforests?
A. Bare land warms absorbs heat and warms the surrounding air faster than forested areas.
B. The erosion of thin, fragile tropical topsoils
C. Heavy smoke in the air causes respiration problems for humans
D. A rapid increase of carbon dioxide, faster than photosynthesis can remove the CO₂
Use the diagram below to answer the following question.
Which of the following statements accurately describes the relative age of the fossils in these rock layers?
A) The yellow shell fossils are from 300 million years ago
B)The brown trilobite fossils are from 500 million years ago
C)The brown trilobite fossils are older than the yellow shell fossils
D)The yellow shell fossils are older than the brown trilobite fossils
Answer:
C) The brown trilobite fossils are older than the yellow shell fossils
Explanation:
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What is the difference in climates east and west of the Cascade Mountains in the Pacific Northwest?
There is more cloud cover and more rain in the east of the Cascade Mountains,
O There are colder winters in the west but milder winters in the east of the Cascade Mountains,
O There is more sunshine and less rain in the west of the Cascade Mountains
There are milder winters in the west but colder winters in the east of the Cascade Mountains,
Answer:
There are milder winters in the west and colder winters in the east
Answer:
There are milder winters in the west but colder winters in the east of the Cascade Mountains. or d/4th one
Explanation:
made it easier to read other one
Yolanda is participating in a group discussion. Several of her peers have spoken before her, and she completely
disagrees with them.
Which response is the most positive approach?
O She should tell the other participants that they do not know what they are talking about
O She should ask the moderator to stop the others from talking, because they have no evidence.
She should walk away from the discussion, because the other participants are clearly hopeless.
O She should look at her notes to find an example that shows exactly why she disagrees.
Answer:
D) She should look at her notes to find an example that shows exactly why she disagrees.
Explanation:
Answer:
D
Explanation:
Quick question please help (: 40 points
Suppose a scientist found a new fossil that indicated it was a primitive mammal. Relative dating techniques place the age of this fossil at a much earlier time than mammals were thought to exist. What effect will this finding have on understanding of the history of life?
A.
The split between mammals and nonmammals in the tree of life needs to be shifted back.
B.
A new branch needs to be added to the tree of life.
C.
An existing branch on the tree of life needs to be removed.
D. Other fossils need to be retested to be sure that the ages assigned to them are not in error.
Answer:
d
Explanation:
7. How does the revolution of the Earth around the sun cause the seasons to change?
2 forms of the same gene is?
Answer:
alleles
Explanation:
Different forms of same gene are called alleles.
An individual diploid organism always possesses two doses of the same gene, i.e. two alleles on its pair of homologous chromosomes.
What's the term that describes all the chemical reactions taking place in an orgasm
Answer:
Metabolism
Explanation:
Fill in the blank
The length of __________ of dark period controls _________.
Which of the following types of fats are most associated with heat disease? (They tend to be solid at room temperature)
A. Monounsaturated
B. Polyunsaturated
C. Phospholipids
D. Saturated fats
Answer:
Saturated Fats
Explanation:
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polyunsaturated
Explanation:
all dietary food contains(polyunsaturated)are solid
Someone please tell me the closest planet and the farthest in order 1-8
Answer:
Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
Explanation:
Answer:Closest to farthest: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
Explanation:
What steps of the water cycle are affected by gravity and which by the Sun?
What macromolecules provide instruction for growth
The differences between two molecules include the type of sugar that forms a section
of the molecules and the identity of one of the four nitrogenous bases that make up
another section of the molecules. These two molecules are -
A proteins
B lipids
C nucleic acids
D complex carbohydrates
What is the function of lipids?
How to invasive plants effect negatively and how does removing them effect is positively
Answer:
Invasive plant species have an impact on the diversity of local species, they affect water availability and damage the quality of soil nutrients. Once an alien plant has invaded a habitat, it changes the conditions of that environment. It does so by changing the light, solar radiation and temperature levels in the invaded patches. The quality and availability of food, shelter, nest sites, basking sites and perches are changed for a number of animals.In a few cases, some benefits of alien plants have been reported. For example, they can provide fire wood for local communities or add resources for animal species. But these benefits typically do not surpass the negative effects.
Explanation:
From the giraffe story, give an example of the following:
1. Variation
2. Adaptation
3. A factor affecting the size of a population
Answer:
1. Each Giraffe's neck length is different
2. The tall neck Giraffes reproduced and their off spring inherited their genes
3. A drought occurred.
Explanation:
which of the following cell is also called rechargeable battery. . primary cell., secondary cell,. dry cell., none of these.
Do neurons create synaptic connections between endocrine glands?
yes because i know it. it is form
Where do ETC reactions take place
A cell’s nucleus will divide during mitosis. Whaat process must happened before it can divide?
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At what point should health officials have started to control the spread of Ebola in West Africa? It needs to be an essay.