Answer:
Speed =d/t. 200÷10=21÷1000=0.021 km/h
Explanation:
S=D/T
Cells of the immune system are able to respond to the
presence of invading organisms because they
recognize the
A) antigens present on the invaders
B) antibodies present in invading pathogens
C) DNA pattern in the nuclei of viruses
D) antibiotics released from microbes
Answer:
A) antigens present on the invaders
Explanation:
Antigens are substances (usually proteins) on the surface of cells, viruses, fungi, or bacteria. Nonliving substances such as toxins, chemicals, drugs, and foreign particles (such as a splinter) can also be antigens. The immune system recognizes and destroys, or tries to destroy, substances that contain antigens
Which of the following is an oxidation-reduction reaction? Fe2O3 3CO Right arrow. 2Fe 3CO2 CuSO4 2NaOH Right arrow. Cu(OH)2 Na2SO4 2NaOH H2CO3 Right arrow. Na2CO3 2NaOH Pb(NO3)2 Na2SO4 Right arrow. 2NaNO3 PbSO4.
The reaction, Fe2O3 + 3CO------> 2Fe + 3CO2 is an oxidation-reduction reaction.
An oxidation-reduction reaction is a reaction in which there is a change in oxidation number from left to right in the reaction. This is because, a specie is oxidized and another specie is reduced.
In the reaction; Fe2O3 + 3CO------> 2Fe + 3CO2, we can see that the oxidation number of iron decreased from +3 on the left hand side to zero on the right hand side. The oxidation number of carbon was increased from + 2 to +4.
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Answer:
A
Explanation:
EDGE2022
Significant digits for the number 80
Answer:
8 and 0
Explanation:
8 and 0 together make 80
how many moles of oxygen molecule is reacting with sodium according to the following reaction:
2Na+O - Na2O2
1 mole of oxygen.
Answer:
solution given:
[tex]2Na+O_2=Na_2O_2\\2mole\:\: 1mole \:\: 1mole[/tex]
according to the above reaction,1 mole of oxygen is required to react with 2 moles of sodium to form sodium peroxide.
Explanation:
How many atoms of carbon are present in 4.10 moles??!
Answer:
2.4×1024 atoms.
Explanation:
Please mark me as brainliest
Calculate the molar mass for CO
Answer:28.01 grams
Explanation:
explain how redox reactions are involved in energy exchanges
Redox reactions involve one substance losing electrons (oxidized) and another substance gaining electrons (reduced) in the same reaction. As electrons are transferred between substances, the electrons lose potential energy and energy is released.
Write the scientific term "A number used by Bohr in the explanation of the spectrum of hydrogen atom and designated by the symbol (n) " ?
Answer:
Quantum number
Explanation:
(07.05 HC A scientist investigating electrically-charged objects has decided to test if the number of times you rub a cloth against a balloon increases the amount of time it will stick to the wall. She wrote down her variables in a table. Variable Description Test The numbers of times she rubbed the cloth against the balloon Outcome The length of times the balloon sticks to the wall Control The cloth used in the experiment What would be her hypothesis for this experiment? (2 points) If you stick the balloon to a wall, then it will become electrically charged and stay there for a long period of time If you change the cloth used to change a balloon
Answer: the answer is b
Explanation:I took the test and got it
pls mark as brainliest if correct for you
The amount of energy involved when an electron is acquired by a neutral gaseous atom is what?
Look at the diagram below. What type of bond does it show?
Explanation:
it shows covalent bonds
The type of bond the diagram shows is covalent bond. As shown the sharing of electrons in the diagram.
What are bonds?Bonds are defined as any of the interactions that lead to atoms joining together to form molecules, ions, crystals, and other stable species that make up the familiar materials found in everyday life. The ability to build molecules is made possible by a chemical bond, which is a strong attraction between atoms, ions, or molecules. Chemical bonds that hold molecules together also form temporary connections vital for life.
Covalent bond are defined as a type of chemical link where atoms share electrons to create electron pairs. Low melting and boiling temperatures, low vaporization heat, low water solubility, and poor conductivity are four characteristics of covalent compounds.
Thus, the type of bond the diagram shows is covalent bond. As shown the sharing of electrons in the diagram.
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In 1980 the Mt. St. Helens volcano erupted and impacted thousands of square miles of forest.Some areas are still undergoing secondary succession where
Answer:
Explanation:
1: Pioneer species are the first to colonize: During primary succession in lava on Maui, Hawaii, succulent plants are the pioneer species. After weathering breaks down the lava into the soil, the plants are able to take root. These plants will help to further change the soil by adding nutrients to it.
The first organisms to appear in areas of primary succession are often mosses or lichens. These organisms are known as pioneer species because they are the first species present; pioneer species must be hardy and strong, just like human pioneers.
2. Is the following sentence true or false? Most earthquakes generate
tsunamis.
I need to right a journal entry for school but i don't know what to put Write a journal entry from the perspective of a particle of light,
called a photon. Your story should follow the photon as it
travels from a star in the Milky Way that is 25 light years away
from Earth, all the way to the eye of a young person gazing up
at the night sky through their bedroom window. Compose your
entry in complete sentences.
it is for my 5 grad sicenc
Answer:
here you go
Explanation:
someone help me on this but i still got a hundred
Why is salt a mineral
Carbon-14 emits beta radiation and decays with a half life of 5730 years. Assume you start with 2.5x10^15 grams of Carbon-14, how many grams remain at
the end of 5 half lives?
A. 1.1x10^-10 g
B. 2.5x10^-10 g
C 1.3x10^-10 g
D. 5.0x10^-10 g
The amount remaining at the end of 5 half-lives is 7.81×10¹³ g
From the question given above, the following data were obtained:
Half-life (t½) = 5730 yearsOriginal amount (N₀) = 2.5×10¹⁵ gNumber of half-lives (n) = 5Amount remaining (N) =?The amount remaining can be obtained as follow:
N = 1/2ⁿ × N₀
N = 1/2⁵ × 2.5×10¹⁵
N = 1/32 × 2.5×10¹⁵
N = 0.03125 × 2.5×10¹⁵
N = 7.81×10¹³ g
Therefore, the amount remaining after 5 half-lives is 7.81×10¹³ g
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please please answer this question!!!!!!
cell membrane - phospholipd bilayer
pigmented - chloroplasts
chloroplasts - oval shaped with two membranes
rectangular or cubed - plant cell
nucleus - control centre
hope that's what you are looking for
BRAINLIEST TO FIRST RIGHT ANSWER
Students were investigating heat transfer by conduction and they set up the simple experiment you see here. They utilized three spoons made of different materials: the specific heat capacity of each material was recorded in the students' data table. Each spoon was placed in a pot of hot (90°C) water and a pat of butter was placed on the handle of each spoon. The butter melted first on the tin spoon and in about the same amount of time on the plastic and wood spoons. Based on the data table and the experimental results select ALL of the conclusions that are appropriate.
A) Conduction occurred more readily in the tin due to its lower specific heat
capacity
B) Heat transfer via conduction occurred from the hot water to the spoons
and then to the butter,
C) When in contact with hot water, there was no transfer of kinetic energy
through the wood or plastic
D) The atoms in the tin spoon vibrated and collided at a greater rate thon
those in the wood or plastic spoons
E) In all three cases energy s transferred from the faster moving hot water
molecules to the slower moving molecules in the spoon
Answer:
the Answer is A B D
Explanation:
the cunduction in the spoons are equal to all the following answers
Conduction occurred more readily in the tin due to its lower specific heat capacity, Heat transfer via conduction occurred from the hot water to the spoons and then to the butter, The atoms in the tin spoon vibrated and collided at a greater rate thon those in the wood or plastic spoons. Thus option A,B, D are correct.
What is specific heat ?
Specific heat can be measured as the quantity of heat required to increase the temperature of one gram of a substance by one degree Celsius.
The units of specific heat are represented as calories or joules per gram per Celsius degree such as the specific heat of water is 1 calorie per gram per Celsius degree
Specific heat capacity= Heat quantity/ mass × change in temperature.
If Q is the quantity of heat in joules, M is the mass of substance heated,
If ∆O is the change in temperature in Kelvin, Then Q= MC∆O, C is a constant called Specific heat capacity. Therefore, making C the subject of formula:
C= Q /M∆O
Thus option A,B, D are correct.
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Rank the following in terms of increasing ionization energy: Sulfur, oxygen, hydrogen, and fluorine.
Answer:
Ranked from lowest to highest:
Sulfur - 999.6 kJ/mol
Hydrogen - 13.5984 kJ/mol
Oxygen - 13.6181 kJ/mol
Fluorine - 17.4228 kJ/mol
Using the periodic table, choose the more reactive nonmetal.
Br or As
Br and As:
Bromine is more reactive as reactivity increases on moving from left to right in p-block
What is the enthalpy of combustion when 1 mol C6H6(g) completely reacts with oxygen? 2C6H6(g) 15O2(g) mc001-1. Jpg 12CO2(g) 6H2O(g) â€""6339 kJ/mol â€""3169 kJ/mol 1268 kJ/mol 6339 KJ/mol.
The enthalpy of combustion of 1 mole of benzene is 3169 kJ/mol .
The first step in answering this question is to obtain the balanced thermochemical equation of the reaction. The thermochemical equation shows the amount of heat lost or gained.
The thermochemical equation for the combustion of benzene is;
2 C6H6(l) + 15 O2(g) → 12 CO2(g) + 6 H2O(g) ΔrH° = -3169 kJ/mol
We can see that 1 mole of benzene releases about 3169 kJ/mol of heat.
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Answer:
-3169 kJ/mol
Explanation:
kcal/mole
EE E E
SODIUM
1s 2s 2p 3s
118
1091
1653
MAGNESIUM 1s 2s 2p 3s2
175
345
1838
2526
ALUMINIUM
1s 2s 2p 3s 3p
138
434
656
2767
If the valence electrons were removed, what would be the lon charge of the element?
Na =
O-1
+1
0-3
+3
Answer:
+1
Explanation:
your removing a electron and it was already balanced
Why are the melting and boiling points of an
element or a compound are called its fixed points.
Substances having fixed chemical proportions will have fixed boiling and melting points. This is the reason that Pure substances have specific melting and boiling points because their chemical proportions are fixed. Mixtures melt and boil over a range of temperatures
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Which atom has the largest atomic radius? *
1.Cl
2.F
3.I
Answer: 2
Explanation:I think
which of the following substances is most soluble in water
a). table salt
b). baking soda
c). Epsom salt
d). table sugar
Answer:
Table salt
Explanation:
Is most soluble in water
Where are nonmetals located in the periodic table?
Question 8 options:
along the upper left side
in the middle
along the upper right side
along the bottom
Answer: They are located along the upper right side of the periodic table.
Explanation: Malleability is a physical property that some elements of matter have that can be broken down into sheets to give them a certain shape without breaking. This physical property belongs to plasticity. It is a characteristic that some metals have, sheets of said metal can be obtained. The heat needs to be increased, some examples are gold, platinum, zinc, tin, etc.
The barometric pressure in Breckenridge, Colorado (elevation 9600 ft) is 580 mmHg. How many kPa is this?
Answer:
1 atmospheric pressure = 760.0 mm Hg
Thus 580 mm Hg = (580 mm Hg/(760 mm Hg/atm))
= 0.763 atm
what activity occurs in the process of photosynthesis
Answer:
Photosynthesis is the process in which light energy is converted into chemical energy in the form of sugars. In a process powered by light energy, glucose (and other sugars) molecules are created from water and carbon dioxide, while oxygen is released as a by-product.Explanation:
i'm mexican
Name these ionic compounds
12. Ag3N
13. NaF
14. Ba
15. Na2S
16. AIBr;
17. LiN
18. KF
19. Srl2
20. Mgo
21. Al2O3
22. CaH2
12. silver nitride
13. Sodium fluoride
14. barium
15. sodium sulfide
16. aluminium bromide
17. lithium nitride
18. potassium sulfide
19. strontium iodide
20. magnesium oxide
21. aluminium oxide
23. calcium hydride
where does oxidation occur in an electrochemical cell