1. ASSERTION AND REASONING QUESTIONS:
In the following questions, a statement of assertion (A) is followed by a statement of reason (R).
Mark the correct choice as:
(a) Both assertion (A) and reason (R) are true, and reason (R) is the correct explanation of
assertion (A).
(b) Both assertion (A) and reason (R) are true, but reason (R) is not the correct explanation of
assertion (A).
(c) Assertion (A) is true, but reason (R) is false. (d) Assertion (A) is false, but reason (R) is true
1) Assertion: Atom is electrically neutral.
Reason: A neutral particle, neutron is present in the nucleus of atom.
2) Assertion: Maximum number of electrons that can be accommodated in L-shell is 8 Reason: The formula to find maximum number of electrons in a shell is 2n2.
3) Assertion: For noble gases, valency is zero.
Reason: Noble gases have 8 valence electrons
4)Assertion: The Nitrogen atom loses its 3 valence electrons to form its ion Reason: Nitrogen ion is an anion
II CHOOSE THE CORRECT ANSWER:
1.An atom has 4 electrons and 4 protons and 4 neutrons. The atom is electrically neutral.
Which difference in the properties of protons and electrons affects the electrical neutrality (c) Electrons and protons have opposite charges of the same magnitude
of the atom?
(a)Electrons are 2000 times lighter than protons.
(b) Electrons and protons have the same charge and mass.
(d) Electrons are present in the outer side of the atom compared to the protons..
Answers
Answer:
1) B
2) A
3) A
4) D
Explanation:
An atom is neutral because it contains an equal number of protons and electrons. Though the atom actually contains neutrons, this reason does not explain the electrical neutrality of the atom.
The L shell actually contains eight electrons because the maximum number of electrons accommodated in each shell is given by 2n^2 where n is the principal quantum number. Since the L-shell corresponds to n=2 then the reason is the correct explanation of the assertion.
The valency of atoms is determined by the number of electrons in the outermost shell of the atom. Remember that atoms having a filed valence shell(eight electrons in the outermost shell) have a valency of zero. Hence the noble gases possess a zero valency. Thus the reason is the correct explanation of the assertion.
Nitrogen forms its ion by electron gain and not by electron loss because nitrogen forms an anion. This anion is formed by a gain of three electrons. The assertion is false but the reason is true.
Related Questions
what is closer to the equator 10 degrees south or 20 degrees north
Answers
Answer:
10 degree north
Explanation:
Hope it helps:)
Rapid cell proliferation can result from:____.
a. a cell ignoring a negative growth regulator.
b. contact inhibition.
c. a mutation inhibiting the action of a positive growth regulator.
d. the surgical removal of a benign polyp.
Answers
Answer:
a. a cell ignoring a negative growth regulator.
Explanation:
Hope it helps :)
What happens in a warm front?
A. A warm air mass becomes a cold air mass as it moves.
B. A warm air mass catches up to a moving cold air mass, sliding
over it.
C. A cold air mass comes in under a warm air mass.
D. A warm air mass collides with a stationary cold air mass, and
slides under it.
Answers
Answer:
A warm front forms when a warm air mass pushes into a cooler air mass, shown in the image to the right (A). Warm fronts often bring stormy weather as the warm air mass at the surface rises above the cool air mass, making clouds and storms. ... As the front passes over an area, the clouds become lower, and rain is likely
3.what colour does the clear alcohol become once the leaf is boiled in it? Explain why?
Answers
Answer:
We boil the leaf in alcohol when we are testing it for starch because to remove the green pigment chlorophyll present in it. For the starch test, we need to observe the colour change from brown to blue when iodine is put on the leaf.give your own position on xenophobia in South Africa
Answers
Answer:
Deprivation, competition for jobs, commodities and housing etc are the causes of xenophobia.
Explanation:
There is a great xenophobia occur in South Africa because of many causes such as deprivation, competition for jobs, commodities and housing etc. Xenophobia is refers to hatred of local people against people belongs and come from other countries. xenophobia attacks occur in South Africa in the year 1994 and 2008 in which immigrants faced discrimination and violence in South Africa that leads to the death of many people.
A humans eye color results from incomplete dominance. If two people with brown eyes were to have children, the possibility of having a child with blue eyes is
a. %6.25
b.%12.5
c.%50
d. %99
please help
Answers
Answer:
A
Explanation:
The lowest percentage due to then both having same color eyes
What level of organization is formed when many cells come together ?
Answers
Answer: A (Tissue)
Explanation:
Cells are the simplest level of organization. Many cells working together form tissue. The cells involved are specialized to cooperate with each other to accomplish one common goal. There are many different types of tissue in both plants and animals. When there are layers of tissue working together, they form an organ.
Hope This Helps!
Answer:
Its tissue
Explanation:
when it comes to the levels of organization cells come first the tissue
How do lungs help cells in the body meet their needs?
A. They produce oxygen for the body.
B. They bring oxygen from air into the body.
O c. They transform oxygen from the body into carbon dioxide.
D. They release oxygen fromod and send it through the body.
Answers
The lungs don’t produce or release oxygen so it’s not A. or D. The lungs do not transform oxygen into carbon dioxide cause our bodies need oxygen not carbon dioxide so it’s not C. Hope this helps!
A gene variation that is masked in the presence of dominant alleles.
Answers
Answer:
Some genes mask the expression of other genes just as a fully dominant allele masks the expression of its recessive counterpart. A gene that masks the phenotypic effect of another gene is called an epistatic gene; the gene it subordinates is the hypostatic gene.
Explanation:
What are the potential hazards relating to materials handling injuries?
Answers
Exceeding load limits.
Falling caused by improperly stored materials.
Poorly maintained lifting devices.
Damaged racking & storage units.
Material handling whilst on ladders, stools, etc.
True or false Jesse and Ray have decided to have sexual intercourse. Ray
has been with one other partner prior to Jesse. They plan on using a
condom to protect against any STls. Jesse, who has never had sex before,
does not need to worry about getting an STI since they will be using a
condom.
Answers
Answer:
False.
Explanation:
There could be rips, holes, or the condom may fail. Condoms only HELPS lower your chances for STI's/STD's.
Which interaction involves only one of Earth's spheres?
Answers
Answer:
Energy stored in plants is transferred to humans and animals that eat them. Biosphere is a sphere on earth where living organism forms a biotic community.
Explanation:
Which would be considered an ecosystem?
A
a colony of bacteria
B
biotic factors in a forest
с
populations of zebras and lions
D
living and nonliving things in a pond
Answers
Answer:
A colony of ants is a species, C is only animals and only the biotic factors it is D living and nonliving things in a pond
Explanation:
Which property refers to how energy, such as heat and electricity, can travel through a material?
Answers
Answer:
Conductivity
Explanation:
The ability of electrical energy to flow through materials is called conduction, so the property is the conductivity property
You are screening three new pesticides for potential mutagenicity using the Ames test. Two his- strains resulting from either a frameshift or a transition mutation were used and produced the following results (number of revertant colonies):
Strain 1
Transition Mutant Control (no chemical) Transition Mutant + Chemical Transition Mutant + Chemical + Rat Liver Enzymes
Pesticide#1 21 180 19
Pesticide#2 18 19 17
Pesticide#3 25 265 270
Strain 2 Framshift Mutant Control (no chemical) Framshift Mutant + Chemical Framshift Mutant + Chemical + Rat Liver Enzymes
Pesticide#1 5 4 5
Pesticide#2 7 5 93
Pesticide#3 6 9 7
Required:
What type of mutations, if any, do the three pesticides induce?
Answers
Answer:
- Pesticide 1: Induces transition mutations. Rat liver enzymes convert it into a nonmutagenic product. Does not induce frameshift mutations.
- Pesticide 2: Does not induce transition mutations. Rat liver enzymes convert it into frameshift mutagen.
- Pesticide 3: Induces transition mutations. Rat liver enzymes don't have ability to convert compounds into mutagens. Does not induce frameshift mutations.
Explanation:
The Ames test is a technique widely used to evaluate the mutagenic potential of a particular chemical compound. The Ames test uses Salmonella typhimurium strains with a defective mutation that makes them unable to synthesize histidine. When the mutation is reversed, then the revertant strains can grow on a medium lacking histidine. A positive test shows that the chemical is mutagenic because its activity is associated with the reversed mutation and thereby the mutant gene regains its function. In humans, as well as in other mammals, many chemicals don't have mutagenic effects themselves but they may become converted into mutagens when are metabolized by the body. For that reason, rat liver enzymes are added to replicate the metabolic effects of the chemical compound being tested. Nowadays, current tests can express recombinant human proteins instead of rat liver enzymes, thereby enabling a better correlation between mutagenic activity and human metabolic processes.
Assume that Brown (B) hair is dominant over blond (b) hair and that oval shaped eyes (O) were dominate over round (o) eyes. Complete a Punnett square showing a cross between a mother who was heterozygous for both traits and a father who also was heterozygous for both traits. Based on Mendel’s work what could you predict about this cross? What percent chance do these parents have that the child will be blond with oval shaped eyes? What percent chance do the parents have that the child will have brown hair with oval eyes? What percent chance do the parents have that the child will have blond hair with round eyes?
Answers
Answer: 25%
Explanation:
So basically, you draw two Punnett Squares, one for each of the different traits. Since both parents are heterozygous, meaning they have a combination of traits, you would label the four sides of the square B, b, B, and b. Same thing with the eye shape trait. Label the sides O, o, O, and o. Then, you plot it like in the picture I provided. When the B and the B match up, label it BB. When the B and the b match up, label it Bb, etc. Then, since your chances of getting blonde hair (bb) is 1 in 4 (4 combinations total), the percentage of getting blonde hair is 25%. Same thing for getting round eyes, just repeat the process. Now that you have all your squares filled, you can see that your chances of getting both blonde hair and round eyes is 2 in 8, which simplifies to 1 in 4, which is equal to 25%
which of the following is a good effect soil erosion
A. clogging of irrigation
B. decrease of food production
C. deposition of mine tailings
D. shaping of landforms
Answers
Answer:
i think shaping of landform is the good effect of soil erosion
Answer each question, using it as an opportunity to illustrate the depth of your knowledge in this area.
1. One of the fundamental controls which ecosystems exert over individual species is limits on population size. This is done by a combination of predatory, competitive, parasitic and mutualistic relationships within the ecosystem. Never the less, the human population has increased well beyond what is healthy for those systems. How did we manage to grow beyond these limitations?
2. Natural variations in weather patterns have effects on certain populations. A warm damp spring for example, is ideal for small rodent species and certain insects, who benefit from the lush vegetation produced by this pattern. As a result, their populations swell to high levels. In the end however, this doesn't result in population growth at the higher tropic levels. You don't end up with more predators, just fatter predators. What limits the ability of the higher tropic levels to grow in response to the increased availability of food?
3. An unfortunate series of events finds you stranded on a remote uninhabited south Pacific island, with little chance of being rescued. It is a modest-sized island with adequate resources to support you, if you are careful to minimize your impact on it. You know that inserting yourself into this ecosystem will almost certainly mean the loss of members in some populations, so your goal is to minimize your impact on the overall biodiversity of the system. With this in mind, from which tropic level(s) should you obtain your food?
Answers
Answer:
1. Humans are an “invasive species” because human populations have eliminated many ecological relationships, dramatically changing the dynamic of their ecosystems
2. continued loss of energy due to metabolic activities
3. lower trophic levels
Explanation:
1. An invasive species is any organism that is not native to an ecosystem and may negatively alter its new environment. Invasive species don't interact with native species when they are introduced into an ecosystem (for example, invasive species usually don't have any natural predators). Humans are an 'invasive species' that occupy a wide range of habitats and whose presence has caused the extinction of many native plants and animals. Human populations have drastically reduced the biodiversity of different ecosystems by competing with native species for limited resources, and we also have altered their habitats (global human population growth is also due to medicine and farming techniques, reducing hunger and diseases). In this regard, it is important to highlight that the human population can also grow in an ecologically sustainable manner by taking care of the ecosystems we live in.
2. Animals (predators) are consumers, thereby they depend on lower trophic levels for their food supply. The Second Law of Thermodynamics indicates that the continual loss of energy due to metabolic activities at lower trophic levels leads to a decrease in the amount of available energy at higher trophic levels. In consequence, the population size decreases at higher levels due to the amount of energy available from one lower level to the next higher level has to decrease when it is used for metabolic activities (i.e., growth, development, etc).
3. In the food chain, the primary producers are found at the lower trophic level (e.g., plants). Primary producers are followed by consumers (e.g., herbivores), they are followed by secondary consumers (i.e., carnivores that eat herbivores), and so on. When an invasive species at higher trophic levels is introduced into a new ecosystem (in this case, human species), it is imperative to preserve the biodiversity (and consequently also the productivity) at lower trophic levels because they are fundamental for the survival of higher trophic levels (i.e., consumers).
PLEASE HELPPP
A Korean male dies at 1:52 pm. When his body temperature
was taken, 12 hours later, it was 86.4" F. Which of the
following BEST explains why this temperature would be
skewed?
1. Ambient temperatures must be higher than
room temperature
1. Ambient temperatures must be lower than
room temperature
K. The victim must have died unclothed
L. The investigator must have been careless in
their calculations
Answers
The temperature is skewed because ambient temperatures must be lower than room temperature. Therefore, option B is correct.
Why the temperature is skewed?The body temperature of a deceased individual normally drops after death due to the cessation of metabolic processes. This process is known as postmortem cooling or algor mortis. The rate of postmortem cooling depends on several factors, including the ambient temperature of the environment in which the body is located.
In this case, the body temperature was taken 12 hours after the individual's death, and the recorded temperature of 86.4°F suggests that the ambient temperature of the environment was lower than room temperature.
This is because the normal room temperature for most indoor settings is around 68-72°F, and a body temperature of 86.4°F after 12 hours of postmortem cooling is abnormally high. Thus, option B is correct.
Learn more about body temperature, here:
https://brainly.com/question/23270157
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PLEASE HELP!!!
What is a species that has been studied in great detail and is used to understand specific phenomena in biology? (ther are no answer choices btw)
Answers
Directions: Select ALL the correct answers
All living things contain carbon. Which of the following statements are true about carbon atoms?
A single molecule of some compounds can contain thousands of carbon atoms.
Each carbon atom can form single bonds with up to four other carbon atoms,
Each carbon atom can form double bonds with up to two other carbon atoms.
0 0
Carbon atoms can join together to form chains or rings,
Reset
Submit
Answers
Describe at least two costs and two benefits of wind farms. !!!! ASAP plzz
Answers
Wind power is cost-effective. ...
Wind creates jobs. ...
Wind enables U.S. industry growth and U.S. competitiveness. ...
It's a clean fuel source. ...
Wind is a domestic source of energy. ...
It's sustainable. ...
Many factories release carbon dioxide directly into to atmosphere. The carbon dioxide would be considered an)
A) primary pollutant
B) placer deposit
C) invasive species
D) secondary pollutant
E) scrubber
Answers
Evolution best explains
O
the biological changes in species over time
O
how organisms obtain energy
why organisms originally came into existence
O
O
the ways organisms grow and develop
Answers
Now use the Frequency slider to increase the frequency to a high value. Compare the motion of the parti
Answers
Answer:
Now use the Frequency slider to increase the frequency to a high value. Compare the motion ofthe particles when the frequency is high to the low-frequency ...
Missing: parti | Must include: parti
Explanation:
PLEASE HELP!!!
What species that has been studied in great detail and is used to understand specific phenomena in biology?
Answers
Answer:
Species that has been studied in great detail and is used to understand specific phenomena in biology are Model organism .
Explanation:
MODEL ORGANISM - A model organism (often abbreviated to model) is a non-human species that has been extensively studied in order to better understand specific biological processes, in the hope that observations made in the model organism can lead to new understanding of the workings of other organisms. When human experimentation is either impossible or immoral, model organisms are commonly used to study human disease. The shared descent of all living species, as well as the survival of metabolic and developmental processes and genetic material during evolution, make this strategy possible.
Although studying model organisms can be beneficial, caution should be exercised when extrapolating results from one organism to another.
Viruses, as well as model organisms from all three realms of life, are included. Escherichia coli (E. coli) is the most widely studied prokaryotic model organism, having been studied for more than 60 years.
It's a common gram-negative gut bacterium that can be easily and cheaply grown and cultured in a laboratory environment. It is the most commonly used organism in molecular genetics, as well as an important species in biotechnology and microbiology, where it has acted as the host organism for most recombinant DNA research.
Hence , the answer is model organism .
brown eye color is dominate; blue is recessive.if a brown-eyed man marries a blue-eyed woman and they have a brown eyed boy and a blue eyed girl, what can we conclude about the parents?
Answers
Answer: first baby - dads dominant brown colored eyes
second baby - both of moms genes becuase you need two recessive genes to have a recessive trait
Explanation: i hope that makes sense, have a great day!!
What if constitution adoption?
Answers
Answer:
in your gaze I lost myself
Explanation:
porque eres linda mi amor
Why mouse is called direct input device ?
Answers
Answer:
because you insert it manually and directly with a cable.
pls mark as brainliest lol
Answer:
A mouse is called direct input device because it is moved by the human/robot user, inputting the signal on where the cursor should go and what actions the cursor does.It also allows you to input and send data to the computer.
.
1. A population is:
A a group of one species in the same place at the same time
B a group of different species in the same place at the same
time
C all the organisms of one species in the same place at the
same time
D all the organisms of different species in the same place at
the same time
Answers
Answer:
D
Explanation:
Because the population is the group of Orgainsms of different species living in one habitat.