Answer:
Gasoline is very volatile and if not kept in a tightly sealed container will quickly fill a space with vapors at a sufficient concentration to be a fire and explosion hazard. Don't even THINK about keeping gasoline in an open container. Well, you can if it is a dense and heavier-than-air gas.
Explanation:
Which of these is the basis for some traditional calendars?
A-cycles of the moon
B-constellations in the heavens
C-solar and lunar eclipses
D-the appearance of seasonal rainstorms
Answer:
A-cycles of the moon
Explanation:
The people of Ancient Greece, Rome and China counted their year based on a 12 moon cycle ( that is, about 354 days). A 13th cycle of the moon is included so that the lunar year remains in step with the seasons of the year.
Today, the Gregorian calendar is mostly used around the world. This calendar was
actually adapted from an earlier lunar version. Ancient civilizations used the phases of the moon to help identify the seasons.
The major difference between the lunar calendar and the solar calendar is the kind of celestial body that is used to determine time.
Question 13 (1 point)
What is the number of neutrons for Silicon-31
14
31
15
29
Answer:
the number of neutrons for silicon is 14
Table salt is sodium chloride and has the chemical formula of NaCl. What is the ratio of sodium atoms to chlorine atoms? (8.5D)
Answer
А 2:1
B
1:1
С
1:2
D
3:1
Answer:
Explanation:Table salt is sodium chloride and has the chemical formula of NaCl. What is the ratio of sodium atoms to chlorine atoms? (8.5D)
Answer
А 2:1
B
1:1
С
1:2
D
3:1
WORTH 25 POINTS
PLS..!!!!!
Primary consumers _____.
a. receive energy directly from the sun
b. make their own food using photosynthesis
c. break down dead matter into chemical nutrients
d. are the first to receive energy from a plant
Answer: D. Are the first to receive energy from a plant.
Explanation: Paying attention to the trophic level in which the food chain occurs is key. Producers are the ones that receive energy directly from the sun. They also make their own food using photosynthesis. A decomposer is the one who breaks down dead matter into chemical nutrients. Therefore, Primary consumers are the first to receive energy from a plant.
I hope this helped!
Good luck <3
please do this i have 7 mirw min to submit
Answer:
1:C
2:D
3:E
4:A
5:B
Explanation:
Please I need it asap
Answer:
I not understand your questions
Answer:
i think is A.
Explanation:
Someone help explains these question pls x
1. Isotopes: the same element, the same atomic number, but different mass numbers
Atomic mass: the average atomic mass of all its isotopes
The mass of an atom of carbon-12= 12 amu ( atomic mass unit) because it has a stable nucleus
[tex]\tt RAM~X=\dfrac{the~average~mass~of~1~atom~X}{\dfrac{1}{12}\times mass~of~atom~C-12 }[/tex]
So RAM relative to isotopes Carbon-12 (C)
2. Ionic Formula is formed from cation(positive charge) and anion(negative charge)
Cation : Na⁺ ( positively charged 1)
Anion : SO₄²⁻ (negatively charged 2)
The anion cation's charge is crossed , then the compound :
[tex]\tt \boxed{\bold{Na_2SO_4}}[/tex]
3. pH is the degree of acidity of a solution that depends on the concentration of H⁺ ions. The greater the value the more acidic the solution and the smaller the pH.
pH = - log [H⁺]
[H⁺] = 0.00001 M = 10⁻⁵ M
[tex]\tt pH= -log 10^{-5}\\\\pH=5~log~10\\\\pH=\boxed{\bold{5}}[/tex]
Was Aristotle atomic theory correct ?
Answer:
No, it is not.
Explanation:
Please answer all questions and explain, except 1, 7, and 8, I will award brainliest. PLEASE HELP ASAP
2. Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons and electrons.
3. Electrons
4. Titanium- Ti
5. a. e and p = 35, n = 45
b. e and p = 46, n = 60
c. e and p = 55, n = 78
6. Barium - atomic number = 56 and mass = 138
Hope it helps :)
Mark it Brainliest pls :)
Answer:
i believe this is ur answer-138
Explanation:
hope this helps :)
In a convection current, hot, less dense, floating particles are farther away from their heat source. Eventually, they will begin to lose heat. What will happen next?
A.) The particles will lose energy, come closer together, become more dense and sink.
B.) The particles will gain energy, spread apart, become less dense and keep floating.
C.) The particles will lose energy, will spread apart, become less dense and sink.
D.) The particles will gain energy, come closer together, become more dense and sink.
Answer: it’s A
Explanation:
what is another term for the ability to burn?
Answer:
flammable
that's the first thing that popped in my head
Another term for the ability to burn is combustibility. Combustibility refers to the ability of a substance to ignite and burn in the presence of oxygen.
Combustibility is a property that varies among different materials.When a substance is combustible, it means that it can undergo a chemical reaction called combustion, which involves the combination of the substance with oxygen to produce heat, light, and often smoke or flame. Combustion is a rapid oxidation process that releases energy in the form of heat and light.
Examples of combustible materials include wood, paper, gasoline, and natural gas. These substances have the ability to burn when exposed to a spark, flame, or heat source.
It is important to note that not all materials are combustible. Some materials, such as metals, may be non-combustible and do not easily catch fire.
It also allows us to take appropriate precautions when handling and storing combustible substances to prevent accidents and fires.
Learn more about combustibility,here:
https://brainly.com/question/15117038
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In the reference image there is a pie graph illustrating the composition of Earth’s atmosphere. What is the most abundant gas making up Earth’s atmosphere? How much of Earth’s atmosphere is comprised of oxygen
Answer:
Explanation:its catbony
The most abundant gas making up Earth’s atmosphere is nitrogen and 21% of of Earth’s atmosphere is comprised of oxygen.
What is atmosphere?An atmosphere meaning 'vapour, steam', and is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low.
A stellar atmosphere is the outer region of a star, which includes the layers above the opaque photosphere; stars of low temperature might have outer atmospheres containing compound molecules.
The layered composition of the atmosphere minimises the harmful effects of sunlight, ultraviolet radiation, the solar wind, and cosmic rays to protect organisms from genetic damage. The current composition of the atmosphere of the Earth is the product of billions of years of biochemical modification of the paleoatmosphere by living organisms.
Learn more about atmosphere,here:
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a student measures the time it takes for two reactions to be completed. Reaction A is completedd in 12 seconds, and reaction B is completed in 2q seconds. What can you conclude about the rates of the reactions?
A. The rate of reaction A is lower
B. The rates of reation A and B are equal
C. The rate of reaction B is lower
A. The rate of reaction A is lower
Further explanationThe reaction rate (v) shows the change in the concentration (reduction of reactants and product additions ) per unit time
Can be formulated:
Reaction: aA ⇒ bB
[tex]\large{\boxed{\boxed{\bold{v~=~-\frac{\Delta A}{\Delta t}}}}[/tex]
or
[tex]\large{\boxed{\boxed{\bold{v~=~+\frac{\Delta B}{\Delta t}}}}[/tex]
A = reactants
B = product
v = reaction rate
t = reaction time
Time of reaction A : 12 s
Time of reaction B : 2 s
Because reaction speed/the rate of reaction is inversely proportional to the time, then A. The rate of reaction A is lower
An amide may be produced by reacting an acid chloride with
Answer:
An amide may be produced by reacting an acid chloride with ammonia.
Answer:
ammonia
Explanation:
An amide may be produced by reacting an acid chloride with ammonia. An amide may be produced by reacting an acid chloride with ammonia.
Plz help!
What is 1 item that is an element?
Give an example of how the 1 item is an element
Answer:
its a
Explanation:ok
The amount of stored chemical energy is what determines the temperature of a
substance. (1 point)
True
Talse
Answer:
False
Explanation:
Temperature is a measure of the average kinetic energy of the particles of a substance.
Which has the larger ionization energy carbon or nitrogen?
Answer:
nitrogen has an ionization energy of 1400 kJ/mol while carbon has an energy of 1086 kJ/mol. Therefore as expected, nitrogen has higher energy than carbon.
This diagram shows a marble with a mass of 3.8 grams (g) that was placed into 10 milliliters (mL) of water.
Complete Question:
This diagram shows a marble with a mass of 3.8 grams (g) that was placed into 10 milliliters (mL) of water. Using the formula V M D = , what is the density of the marble?
(See attachment for full diagram)
Answer:
1.27 g/cm³
Explanation:
First, find the volume of rock:
Volume of rock = volume of water after rock was placed - volume of water before rock was placed
Volume of rock = 13 - 10 = 3ml
Density of rock = grams of rock per 1 cm³
Note: 1 ml = 1 cm³
Let x represent amount of rock per 1 cm³
Thus,
3.8g = 3 cm³
x = 1 cm³
Cross multiply
1*3.8 = 3*x
3.8 = 3x
3.8/3 = 3x/3
1.27 = x
Density of rock = 1.27 g/cm³
Answer:tbh idek i have a diff one
Explanation:
Which of the following is not a physical change?
A. glass breaking
B. iron rusting
C. ice melting
D. sugar dissolving
Answer:
b or d
Explanation:
What statement about models of isotopes below is accurate?
A- Each picture represents a different element because they have different numbers of neutrons
B- each picture represents an isotope of carbon because they each have 6 protons
C- each picture represents an isotope of lithium because they each have 3 protons
Answer : The correct option is (C) each picture represents an isotope of lithium because they each have 3 protons.
Explanation :
Isotope : It is defined as the element that have the same number of protons but have the different number of neutrons of each of the atom.
As in the given picture, the number of protons are same but number of neutrons are different.
As we know that atomic number is either equal to number of protons or electrons for neutral atom.
The number of protons in the given picture are 3.
So, the element will be lithium with atomic number 3 and all are the isotopes of lithium.
Hence, the correct option is (C) each picture represents an isotope of lithium because they each have 3 protons.
Is most of the bacteria on your body harmful?
Answer:
No it is not, most bacteria is very helpful, it helps the body function and fight off diseases when the body is sick. Sometimes the good bacteria can't fight off the bad bacteria and will cause you to have to buy antibiotics. The antibiotics give the body a huge advantage at fighting off the disease and the body goes back to normal.
does mass change when you add alka seltzer to water??
Answer:
It produces carbon dioxide when an Alka-Seltzer tablet dissolves in water. In the bath, the carbon dioxide dissolves and then emerges as a gas from the solution.
This carbon dioxide gas has mass, but it escapes from the container and diffuses into the atmosphere because it is a gas.
The mass loss from the container is directly calculated by the analytical balance.
a. In the complete reaction of 22.99 g of sodium
with 35.45 g of chlorine, what mass of sodium
chloride is formed?
Answer : 58.44 g
Further explanationThe reaction
[tex]\tt Na+Cl\Rightarrow NaCl[/tex]
mole ratio :
Na : Cl : NaCl = 1 : 1 : 1
Molar mass of Na : 22,989769 g/mol = 22.99 g/mol
Molar mass of Cl : 35,453 g/mol= 35.45 g/mol
Molar mass of NaCl : 58,44 g/mol
Let's check the mol for reactant (Na and Cl) and product(NaCl)
mol of Na :[tex]\tt mol=\dfrac{22.99}{22.99}=1[/tex]
mol of Cl :[tex]\tt mol=\dfrac{35.45}{35.45}=1[/tex]
Then the reactants are completed reacting because it matches the mole ratio, which is 1: 1
so that the mole of the product can be determined from the mol Na or Cl, which is 1
mass of NaCl :[tex]\tt =\dfrac{mol~NaCl}{mol~Na}\times MW~NaCl\\\\=\dfrac{1}{1}\times 58.44\\\\=\boxed{\bold{58.44~g}}[/tex]
5. Which of these elements has the greatest atomic radius? *
Be
Mg
Ra
Ba
"Benzene is an inflammable liquid" is it a chemical property of Benzene
Answer:
df
Explanation:
fawfe
Answer:
yes it is
hope it helps you
What is one way that kinetic energy can be transformed into another form of energy?
Only the _______
valence electrons in an atom take part in chemical bonds.
A)Paired
B)Unpaired
Answer:
A) Paired
Explanation:
hdhwmenrnbdbd
What is the nuclear equation for californium-253 formed by alpha emission?
Answer:
Explanation:
During α-decay, an atomic nucleus emits an alpha particle. ... Note that the sum of the subscripts (atomic numbers or charges) is the same on each side of the equation. Also, the sum of the superscripts (masses) is the same on each side of the equation.Jul 29, 2014
Which of the following terms is a term that could refer to heterogeneous matter? a. element b. mixture c. compound d. solution
Answer : b. mixture
Further explanationElement and compound are included in pure substance where the composition is the same in each part
Elements are made up of 1 type of atom, while the compounds of 2 or more types of atoms , both can be represented in the form of chemical symbols
A mixture is a combination of substances. The properties of a substance in the mixture component are unchanged
The mixture can be a homogeneous mixture or a heterogeneous mixture
the homogeneous mixture if each part has the same composition the heterogeneous mixture if each part has a different compositionSolution including into Homogeneous mixture, while suspension into a heterogeneous mixture
So a term that could refer to heterogeneous matter : b. mixture
Why is it hot in summer and in the winter why is cold
Answer: The sun is closer to the Earth is the summer and farther in the winter causing it to be hotter than it is colder in the summer and vise versa for the other question.
Explanation: I learned it ;)
Explanation:
The earth is tipped on its axis, 23.5 degrees in respect to the sun. In the summer time, the northern hemisphere has slightly more hours of daylight because of this, becoming more extreme as one goes north. If you go far enough north, there is 24 hours of sunlight in high summer.
So the average temperature is higher, because there is sunlight is present for more hours and the earth is warmed on balance.
At the same time, the south pole is in shadow, so the southern hemisphere has winter in June.
Six months later, the 23.5 degree tilt has the north pole facing away from the sun, and with fewer daylight hours, the temperature cools progressively. Meanwhile, the southern hemisphere is having it’s summer in December.