Answer:
SARS was an epidemic, but not a pandemic.
Explanation:
It is correct to say SARS was an epidemic but not a pandemic.
An epidemic is an outbreak of infectious diseases which affects a group of people in a particular areasA pandemic is a global outbreak of diseases that affects the total population of people over a wider range.SARS outbreak occurred between 2002 - 2004 in China. It was localized to the People's republic and hence, an epidemic.
The recent outbreak of disease in 2020 on the other hand is a pandemic. The infectious disease had a global coverage.
Answer:
sars was an epidemic , but not an pandemic
Explanation:
Fossil fuels were formed when living things (plants and animals) died and their remains were broken down. This is an example of _______.
A. Combustion
B. Decomposition
C. Photosynthesis
D. Cellular Respiration
What is the energy of a wave with wavelength of 2.25nm?
Answer:
E = 8.84×10⁻¹⁷ J
Explanation:
Given data:
Wavelength of wave = 2.25 nm (2.25×10⁻⁹ m)
Energy of wave = ?
Solution:
Formula:
E = hc/λ
c = 3×10⁸m/s
h =6.63 ×10⁻³⁴ Js
now we will put the values,
E = 6.63 ×10⁻³⁴ Js × 3×10⁸m/s / 2.25×10⁻⁹ m
E = 19.89×10⁻²⁶ Jm / 2.25×10⁻⁹ m
E = 8.84×10⁻¹⁷ J
Which best blocks X-ray particles and can therefore be observed more closely through the use of this technology?
Answer: The bones block the x-ray particles to pass through it, and a study of the bones is possible using this technology.
Explanation:
Answer and explain please
Answer:
I can only see b
Explanation:
Answer:
Carbon- 11 has 6 protons in its nucleus and boron- 11 has 5 protons in its nucleus.
Explanation:
note: Carbon has an atomic number of 6
and Boron has an atomic number of 5.
SOMEONE PLEASE ANSWER
How many grams are in 15.6 moles of Barium Chloride?
How many molecules are in 156.0g of Iron (II) Sulfate?
How many moles are in 123.0g of Lithium Carbonate?
Convert 1.8 moles of Ca to number of atoms.
How many atoms are in 12.3 moles of Lithium
Answer:You can view more details on each measurement unit: molecular weight of BaCl2 or grams This compound is also known as Barium Chloride. The SI base unit for amount of substance is the mole. 1 mole is equal to 1 moles BaCl2, or 208.233 grams.
Explanation:
Which elements make up the pain reliever acetaminophen, chemical formula C8H9O2N? Of these elements, which is present in the greatest proportion by number of atoms?
a
Calcium, helium, ozone, and neon, with calcium present in the greatest proportion
b
Carbon, hydrogen, oxygen, and nitrogen, with carbon present in the greatest proportion
c
Calcium, hydrogen, oxygen, and neon, with hydrogen present in the greatest proportion
d
Carbon, hydrogen, oxygen, and nitrogen, with hydrogen present in the greatest proportion
Answer:
Carbon, hydrogen, oxygen, and nitrogen, with hydrogen present in the greatest proportion
Explanation:
Let's consider the chemical formula of acetaminophen: C₈H₉O₂N. According to this formula, in 1 molecule of acetaminophen there are:
8 atoms of carbon (C)9 atoms of hydrogen (H)2 atoms of oxygen (O)1 atom of nitrogen (N)As we can see, the element present in the greatest proportion by number of atoms is hydrogen.
what type of bond occurs between a metal and a nonmetal
Answer:
Ionic Bonds - A bond between metal and nonmetal elements. Involves transferring electrons. Covalent Bonds - Also known as molecular bonds. A bond between two nonmetals
Answer:
ionic bonds
Explanation:
A bond between metal and nonmetal elements. Involves transferring electrons.
Which statement correctly describes a characteristic that a scientific
measuring tool should have?
A. To be precise, it must be able to make measurements repeatedly
over a long period of time.
B. To be precise, it must be able to make measurements with small
units.
C. To be precise, it must be able to make measurements that are
close to the actual value.
D. To be precise, it must be able to make measurements with both
large and small units.
Answer:
A. To be precise, it must be able to make measurements repeatedly over a long period of time.
Explanation:
The precision of a scientific measuring tool can be defined as how close the values between multiple measurements are to each other, when repeated under the same conditions.
This ultimately implies that, the precision of a scientific measuring tool reflects the reproducibility and repeatability of its measurements, irrespective of how accurate the measurements are.
In science, one of the most effective ways to determine the precision of a scientific measuring tool is to find the difference between the highest and lowest measurements (measured values).
Hence, the statement which correctly describes a characteristic that a scientific measuring tool should have is that, to be precise, it must be able to make measurements repeatedly over a long period of time.
Lead (11) oxide dissolves in both
excess dilute nitric acid and
sodium hydroxide solution -
Which of the following is the
property of lead (11) oxide.
A Basic
B Acidic
C Neutral
D Amphoteric
Answer:
bacic
Explanation:
it is very soluble in water
please help I will mark brainliest if you answer first let's see who gets brainliest
Answer:
Winter would be warmer, and summers would be cooler.
Answer:
winter would be cooler and summers would be warmer
Explanation: i am hella late but......
how do we grow flowers in vase and plastic bags?
Answer:
put soil in the plastic bag.. put seeds. and add water
Explanation:
this is the right answer
Given 8.55 g of butanoic acid and excess ethanol, how many grams of ethyl butyrate would be synthesized, assuming a complete 100% yield?
Answer: Amount of ethyl butyrate formed = 11.3 g
Explanation: The reaction between butanoic acid (C3H7COOH) and excess ethanol (C2H5OH) is:
Since ethanol is the excess reagent, the formation of the product i.e. ethyl butyrate is influenced by the amount of butanoic acid present
Based on the reaction stoichiometry:
1 mole of butanoic acid produces 1 mole of ethyl butyrate
Mass of butanoic acid = 8.50 g
Molar mass of butanoic acid = 88 g/mol
Moles of ethyl butyrate = 0.097
Molar mass of ethyl butyrate= 116 g/mol
brainless, please
Grams of ethyl butyrate produced : 11.27 g
Further explanationA reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.
The reaction between Butanoic acid-C₄H₈O₂ and an excess Ethanol-C₂H₅OH to produce ethyl butyrate-C₆H₁₂O₂ :
C₄H₈O₂+C₂H₅OH⇒C₆H₁₂O₂+H₂O
mass Butanoic acid- C₄H₈O₂= 8.55 g, so mol C₄H₈O₂ (MW=88,11 g/mol) :
[tex]\tt \dfrac{8.55}{88.11}=0.097[/tex]
[tex]\tt \%yield=\dfrac{actual}{theoretical}\times 100\%[/tex]
For 100% yield ⇒ actual=theoretical
Because Ethanol as an excess, so Butanoic acid as a limiting reactant and mol Ethyl butyrate based on mol Butanoic acid
From equation, mol ratio of mol C₆H₁₂O₂ : mol C₄H₈O₂ = 1 : 1, so : mol C₆H₁₂O₂=mol C₄H₈O₂= 0.097
mass C₆H₁₂O₂(MW=116.16 g/mol)
[tex]\tt 0.097\times 116,16 g/mol=11.27~g[/tex]
How has atomic theory changed since Dalton wrote his postulates?
Select one:
a. Atomic theory has not changed.
b. We have discovered that atoms are made up of smaller particles, called subatomic particles.
c. We have discovered that atoms of one element can change into atoms of another element through chemical reactions.
d. We have discovered that air is not made of atoms.
Answer:
The correct answer is - option b. We have discovered that atoms are made up of smaller particles, called subatomic particles.
Explanation:
Dalton made various postulates related to the atom which is an atomic theory that was first try to describe all properties of atoms. The major part of this atomic theory is that the atoms are unit that makes all the matter which is indivisible.
This postulate of the atomic theory is incorrect and changed as atoms are not indivisible and can divide into subatomic particles (proton, neutron and electron) however atoms are the unit that involves in reaction.
The way in which the atomic theory changed since John Dalton wrote his postulates is that: B. We have discovered that atoms are made up of smaller particles, called subatomic particles.
An atom can be defined as the smallest, indivisible, fundamental unit of matter that forms all chemical elements. Thus, it is the fundamental (basic) building blocks of matter.
The first model of an atom was proposed by a notable English chemist called John Dalton. In the early 1800s, John Dalton adopted Democritus' theory to formulate the first model of an atom.
Dalton's atomic theory postulated that the atom of a chemical element as an impenetrable, indivisible, very small (tiny) but movable hard sphere i.e it cannot be divided into subatomic particles.
However, it has been established by other atomic model that an atom comprises three subatomic particles such as:
ProtonsElectronsNeutronsRead more on atoms here: https://brainly.com/question/377844
8. What is diabetes?
Answer:
Diabetes is a disease that occurs when your blood glucose, also called blood sugar, is too high. Blood glucose is your main source of energy and comes from the food you eat. Insulin, a hormone made by the pancreas, helps glucose from food get into your cells to be used for energy. Sometimes your body doesn’t make enough—or any—insulin or doesn’t use insulin well. Glucose then stays in your blood and doesn’t reach your cells.
Over time, having too much glucose in your blood can cause health problems. Although diabetes has no cure, you can take steps to manage your diabetes and stay healthy.
Answer:
Diabetes is the condition in which the body does not properly process food for use as energy. Most of the food we eat is turned into glucose, or sugar, for our bodies to use for energy. The pancreas, an organ that lies near the stomach, makes a hormone called insulin to help glucose get into the cells of our bodies.
- CDC
Why is fractional distillation not used to produce drinking water from sea water?
Answer:
Please mark me brainliest. the answer is
Explanation:
The problem is that the desalination of water requires a lot of energy. Salt dissolves very easily in water, forming strong chemical bonds, and those bonds are difficult to break. Energy and the technology to desalinate water are both expensive, and this means that desalinating water can be pretty costly.
Fractional distillation not used to produce drinking water from sea water Because single step distillation process is enough to purify sea water.
What is Fractional Distillation ?The separation of a liquid mixture into fractions differing in boiling point (and hence chemical composition) by means of distillation, typically using a fractionating column.
We don’t need fractional distillation but single step distillation to purify seawater.
Fractional distillation is most commonly used to separate various volatile organics out of crude oil as the fractions of the crude have different uses.
Removing water from a solution is a single step process we can easily do at home.
Hence,Fractional distillation not used to produce drinking water from sea water Because single step distillation process is enough to purify sea water.
Learn more about Distillation here ;
https://brainly.com/question/13345735
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Why is a cell membrane like a security guard because.......
Why?????
The cell membrane allows certain items into a cell and blocks others from entering, just like a security guard protects a real factory.
During photosynthesis, plants take carbon dioxide from the air and water and convert them into:
A. amino acids
B. glucose and oxygen
C. oxygen and chlorophyll
D. water and sunlight
Answer:
B.
Explanation:
Glucose and oxygen.
How does the concentration (amount) of carbon dioxide in the affect climate?
A. As carbon dioxide concentrations increase, temperatures decrease.
B. As carbon dioxide concentrations increase, temperatures increase.
C. Carbon dioxide concentrations have no affect on climate.
D. As carbon dioxide concentrations increase, temperatures become more random.
Answer:
A
Explanation:
When the carbon dioxide concentration goes down, temperature goes down. A small part of the correspondence is due to the relationship between temperature and the solubility of carbon dioxide in the surface ocean, but the majority of the correspondence is consistent with a feedback between carbon dioxide and climate.
NEED ASAP!!!
What is another name for acoustical energy?
a.) light energy
b.) electromagnetic energy
c.) mechanical energy
d.) sound energy
Answer:
d.) sound energy
That is the correct answer :)
how many moles is 8.34 x 1022 molecules of NH3
what are examples of chemicals that need to be diluted? i need 4 examples please 20 points!
Answer:
Travelling hygiene
Drink only bottled water.
Don't use tap water to clean your teeth.
When you wash your hands, make sure they are totally dry before you touch any food.
Don't wash fruit or vegetables in unsafe water.
How many orbitals in iron are half-filled, that is, have only one electron?
(A) 1
(B) 2
(C) 3
(D) 4
Answer:
B.
Explanation:
1 orbital is 4 half of 4 is 2.
How many orbitals are in the first energy level?
O A. 3
O B. 1
O c. 2
O D. 4
Question 1 of 10
Using sugar as an alternative fuel source raises many concerns. Which of the
following is not a concern?
A. Sugar may require more energy to produce than it would supply.
B. Sugar may become too expensive for people to make desserts.
C. Sugar can be grown and produced in a relatively short time period.
O D. Sugar might become difficult to find in grocery stores.
SUBMIT
Answer: C.)
Sugar can be grown and produced in a relatively short time period.
The attraction between a positive metal ion and the electrons surrounding
it is a(n)
metallic bond
O ionic bond
chemical bond
covalent bond
Answer:
metallic bond
Explanation:
Metallic bonds are the attraction between a positive metal ion and the electrons surrounding them.
This bond is found in metals and their alloys. They are interatomic forces.
In this bond, a positive nuclei joins with all other closely packed atoms in the lattice and the electron cloud formed by losing their outermost shell electrons. Most of the physical properties of metals is due to this bond type.Help Me Just One Question Okay
What occurs when cells breakdown food to release energy?
A.Respiration
B.Photosynthesis
Answer:
respiration
Explanation:
respiration means break down of food for production of energy
photosynthesis is the process by which plants produce there own food
Given a force of 88 N and an acceleration of 4 m/s2, what is the mass? *
Write the term that is suggested by each figure or description
Students are to imagine that they are leading a one-week expedition to the Moon’s South Pole. In the essay, students will need to describe to NASA what (and who) they would bring to help make their expedition a success.
Answer:
On Sept. 15, 2020, NASA, in partnership with Future Engineers, launched the Artemis Moon Pod Essay Contest. The contest, which is open to all (public, private, and home school) students in grades K-12, asks participants to imagine they are leading a one-week expedition to the Moon’s South Pole. In the essay, students will need to describe to NASA what (and who) they would bring to help make their expedition a success.
The Moon Pod Essay Contest is presented in support of NASA’s Artemis program. The student challenge is part of NASA’s efforts to engage the public in its missions to the Moon and Mars. NASA is returning to the Moon for scientific discovery, economic benefits, and inspiration for a new generation. Working with its partners throughout the Artemis program, the agency will fine-tune precision landing technologies and develop new mobility capabilities that allow robots and crew to travel greater distances and explore new regions of the Moon.
Explanation:
Answer:
I would bring some warm clothes to keep me warm through the night because South Pole is cold. I would also bring blankets and sticks to make a fire. I would bring my bestfriend to keep me company.
Explanation:
Does anyone know how to do this?
Answer:
yes
Explanation:
i don't have the periodic table in front of me right now but you will need it. for the first coloumn, look at the elemnt symbol and write it down. for example hydrogen H. the atomic mass will be written on the bottom of the entry. the atomic number is on the top. the number of protons is the atomic number. the neutrons is atomic mass-atomic number and the electrons you have to count the numbers in the upper right corner. depends what element you look at, there might be a couple rows of the electrons which are the shells. hope i helped :)