Answer:
Combustion is a rapid exothermic chemical reaction between oxygen, O₂, and a substance which is known as the fuel that is initiated by an ignition (heat) source to produce carbon dioxide and water vapor other oxides and combustion products
With the continuous model, which is the model seen with the naked eye, that have uniform parts, the combustion of coal that produces no flammable vapors and hence no flame, the combustion of hydrogen gas which is nearly colorless and the combustion of gasoline that produces a bright flame, burns without flame will be taken as different processes
Explanation:
Which of the following best explains why the ripples that are formed when a pebble is dropped into water eventually stop?
A.
A wave will travel only as long as there is energy to be transferred.
B.
A wave will travel only as long as there is a place for it to move.
C.
A wave will travel only as long as there are water particles.
D.
A wave will travel only as long as it takes the pebble to sink in the water.
Answer: the answer is A
Explanation:
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The half-life of tritium (31H) is 12.3 years. If 57.0 mg of tritium is released from a nuclear power plant during the course of a mishap, what mass of the nuclide will remain after 49.2 years? mg
Answer:
3.57 mg
Explanation:
The following data were obtained from the question:
Half life (t½) = 12.3 years
Original amount (N₀) = 57.0 mg
Time (t) = 49.2 years
Amount remaining (N) =?
Next, we shall determine the rate of disintegration. This can be obtained as follow:
Half life (t½) = 12.3 years
Decay constant (K) =.?
K = 0.693 / t½
K = 0.693 / 12.3
K = 0.0563 /year
Finally, we shall determine the amount remaining after 49.2 years as shown below:
Original amount (N₀) = 57.0 mg
Time (t) = 49.2 years
Decay constant (K) = 0.0563 /year
Amount remaining (N) =?
Log (N₀/N) = kt / 2.303
Log (57/N) = (0.0563 × 49.2) / 2.303
Log (57/N) = 2.76996 / 2.303
Log (57/N) = 1.2028
Take the anti log of 1.2028
(57/N) = anti log (1.2028)
57/N = 15.95
Cross multiply
57 = N × 15.95
Divide both side by 15.95
N = 57 / 15.95
N = 3.57 mg
Thus, 3.57 mg of the nuclide will be remaining after 49.2 years.
William finds a piece of pure iron in his garden. After a few days, the iron begins to rust. What are the two types of substances involved in the rusting process of iron? Iron is with one kind of atom that combines with oxygen from the air to form rust (iron oxide). Rust contains two types of atoms, which means it is .
Answer:
IronOxygenExplanation:
Rusting of iron occurs during the reaction of iron and oxygen in the presence of moisture to form hydrous iron (III) oxide, which is a reddish brown substance.
By virtue of this, the atoms which are reactants in the redox reaction would e oxygen and iron.
I hope this was clear and easy to understand.
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an element
a compound
What happens to the volume of a gas when the pressure increases and the temperature remains the same?
Answer:
This means that if a gas is heated up and the pressure does not change, the volume will. So for a fixed mass of gas at a constant pressure, volume ÷ temperature remains the same. The volume of a gas rises as its temperature is raised Balloons shrink when placed inside a beaker of cold liquid nitrogen
Explanation:
Answer: Amount, if the number of particles and the temperature are constant, is inversely proportional to strain. As the volume increases, there are two options for the strain to stay the same. ... In other words , the number of particles is equal to the volume if temperature and pressure are constant.
durring cellular resperation, chemical energy is converted to cellular energy true or false
What structure in insects allows for oxygen to enter their body?
Answer:
Oxygen travels to insect tissues through tiny openings in the body walls called spiracles, and then through tiny blind-ended, air-filled tubes called tracheae.
The structure in insects that allows oxygen to diffuse into their body is the spiracle.
Insects are animals that belong to the class Insecta in the phylum Arthropoda. They have a segmented body that is divided into 3 majors parts:
The headThe thoraxThe abdomenIn addition, insects have jointed appendages and an exoskeleton made largely of chitinous proteins.
Gaseous exchange in insects is tracheal. The trachea is a network of tubes that lead to openings in the body of insects known as spiracles. In other words, air enters through the spiracle and connects to the trachea tubes where gaseous exchange occurs.
More on gaseous exchange in insects can be found here: https://brainly.com/question/21538375
what information do we need to determine the molecular formula of a compound from the empirical formula?
The elements least likely to form bonds are found in which group?15
16
83
17
18
Answer:
its actually 18 so you dont have to feel lucky
Explanation:
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if an ion has 26 protons and 24 electrons what is the charge on the ion?
Answer:
+2
Explanation:
Protons are positive and electrons are negative, this ion has more positive charges than negative charges therefore the overall charge of the ion is +2.
+26 + -24 = +2
If an ion has 26 protons and 24 electrons, the charge of the ion will be +2.
HOW TO DETERMINE CHARGE OF AN ION:
The charge of an ion can be determined by subtracting the number of electrons from the number of protons in the atom. Charge = no. of protons - no. of electronsAccording to this question, an ion has 26 protons and 24 electrons. This means that the charge of the ion can be calculated as follows:Charge of ion = 26 protons - 24 electrons = +2. Therefore, if an ion has 26 protons and 24 electrons, the charge of the ion will be +2.Learn more about how to calculate charge of an ion at: https://brainly.com/question/14471616?referrer=searchResults
A pure silver necklace melts into liquid at 1,763°F. A pure silver
spoon melts at 1,763°F.
Is the melting point of a substance an example of an extensive or
intensive property? Explain how you know.
Answer:
Intensive property
Explanation:
The melting point of a substance is the temperature at which a solid metal changes to liquid.
At this stage, the particles of the solid would have gained sufficient energy to break away from the well ordered lattice configuration and they begin to behave like liquids.
An intensive property of matter is a physical property of matte that does not change as the quantity of matter changes. Melting point is one of such property. In this problem, we know that the mass of a necklace is lesser compared to that of a pure sliver spoon. But the melting point remains the same. This is pure indication of intensive property.An extensive property changes as the mass of the body changes.
describe the role of a geographer
Answer:
Answer Below
Explanation:
Geographers use maps and global positioning systems in their work. Geographers study the Earth and the distribution of its land, features, and inhabitants. They also examine political or cultural structures and study the physical and human geographic characteristics of regions ranging in scale from local to global.
answer:
a geographer uses maps and global positioning systems in their work to study the earth and the distribution of its land & features & inhabitants and to examine political or cultural structures ranging in scale from local to global.
explanation:
that's the role of a geographer
i answered your question & hope you have a great day!
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The largest element with electrons in two energy levels?
Answer:
alkaline earth metals
Explanation:
group 2A elements are the alkaline earth metals they have two electrons in the outermost energy level because their electron consideration ends in s2. you can add me and I'll help more please give me Brandy is I'm trying to move up I need two more to move up and I'll help you anytime I can
Tijuan mixed a solid and a liquid together in a beaker. He determined that a chemical change occurred. If his conclusion is correct, which substances could he have been observing and why?
Answer:
The production of bubbles indicates that a new substance formed
Explanation:
A chemical change is characterized by the following:
i) A new substance is formed
ii) It is not easily reversible
iii) Heat is evolved
When Vinegar and baking soda are mixed, a gas is evolved. The evolution of a gas indicates that a new substance has been formed, hence a chemical change has taken place.
Answer:
B
Explanation:
edge 2020
A 1.87 g sample of a hydrocarbon gas occupies a volume of 672.0 mL at 35°C and 741 mmHg. What is the molecular formula of the gas in this sample? MC= 12.01 g/mol, MH = 1.01 g/mol, R = 0.0821 L∙atm/mol∙K
Answer:
C₅H₁₂
Explanation:
Using general law of gases we can determine the moles of the sample and, as we know the mass the molecular formula is the ratio between mass in grams per mole of susbtance. With this, we can find the molecular formula, thus:
Moles:
PV = nRT -General gas law-
Where P is pressure: 741mmHg * (1atm / 760mmHg) = 0.975atm
V is volume in liters: 672.0mL = 0.672L
n are moles -Our incognite-
R is gas constant: 0.0821atmL/molK
And T is absolute temperature: 273.15 + 35°C = 308.15K
Replacing:
n = PV/RT
n = 0.975atm*0.672L / 0.0821atmL/molK*308.15K
n = 0.0259moles
And molar mass is:
1.87g / 0.0259moles =
72.2g/mol.
In 72.2g/mol we can have just 5 moles of C:
5 moles of C will weigh: 12.01g/mol * 5 = 60.05g/mol
And the other mass must come from hydrogen:
72.2g/mol - 60.05g/mol = 12.15g/mol / 1.01g/mol = 12 moles of hydrogen
And molecular formula is:
C₅H₁₂A calcium atom will react with two atoms of chlorine to form calcium chloride, CaCl 2. What other element will likely react the same way with chlorine?
Neon
Lithium
Rubidium
Strontium
Answer:
Strontium
Explanation:
Elements are classified into groups and periods. Elements that are grouped together in the same group are said to have the same number of valence electrons, hence, they behave the same way chemically. This is the case of Calcium which reacts with Chlorine to form CaCl2. Calcium belongs to Group II in the periodic table, hence, possesses two valence electrons which it transfers to chlorine atoms.
Strontium (Sr) will behave the same way like Calcium because they belong to the same group in the periodic table, meaning that they both have two valence electrons, which they'll transfer. Strontium will form compound SrCl2 with Chlorine.
Please Help! Chemistry question
Answer:
i think ur right
Explanation:
An __??___ a pure substance. Examples would include oxygen and fluorine.
A. Element
B. Compound
C. Homogeneous Mixture
D. Heterogeneous Mixture
The swe objects shown are made of the same element. What else is true of
O They have the same shape
B They have the same mass
They are made of only one kind of atom
They have the same number of atoms
Answer:
the answer is D
Explanation:
List the formal names and symbols for the four quantum numbers, their alternative names ( if applicable), and all possible values in the ground state of an atom
Answer:
See explanation
Explanation:
There are four sets of quantum numbers, they are;
1) Principal quantum number (n): The values of the principal quantum number ranges from 1 - ∞.
2) Subsidiary/azimuthal/orbital quantum number (l): The values of this set of quantum number ranges from 0-3 corresponding to s, p, d, f.
3) Magnetic quantum number (m): The values of the magnetic quantum number ranges from -l to +l.
4) Spin quantum number (ms): The values of spin quantum number are; -1/2 and +1/2
a truck with a mad of 1500 kg has a negative acceleration of 5 m/s/s, how much forces did this require
Answer:
The answer is 7500 JExplanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × accelerationFrom the question we have
force = 1500 × 5
We have the final answer as
7500 NHope this helps you
what type of bond is this combination most likely to form?
Sodium is a group 1 element with atomic number 1. It has 11 electrons. It is soft reactive metal. It has 1 valence electron.
Fluorine is a group 7 element, a hologen with 7 valence electron. It is a most reactive non metal.
When sodium react with fluorine, ionic bond is formed in the resulting compound sodium fluoride.
One sodium and fluorine each totaling 2 atoms are enough to make the bond.
As the bond is formed, both atoms have octet structure. That is they each have 8 electrons on their outermost shells.
The positive charge on sodium indicates that sodium had lost 1 electron to fluorine atom.
The negative charge on fluorine ion indicates that fluorine atom had gained 1 electron from sodium atom to form negative ion.
The name of the compound is sodium fluoride with formula NaF.
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in what two ways can you increase the elastic potential energy of a bucket of water sitting on a bench brainly
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Which of the following is not a
compound?
CO2, Chi, nací , ci
If you're talking about organic and inorganic compounds, they are all classified under one.
However, if you're talking about ionic and covalent compounds, they can be classified under them.
Carbon dioxide: Covalent
I believe you're talking about ChL, which could be considered a chemical compound or covalent.
NaCi does not exist. However, if you're talking about NaCl, which DOES exist, it is ionic.
Ci does not exist, but if it's Cl, once again, covalent.
Henceforth, I have no context. ChL OR NaCl could be considered the answer.
Why ChL? Chemical.
Why NaCl? It is the odd one out and ionic bonds are often considered a compound different from others.
What is being released into the
atmosphere that is causing
climate change?
Answer:
Greenhouse gases
Explanation:
They are what causes climate change and affects the ozone layer.
why can't you see the salt in seawater
The simple awnser is that it dissolved.
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What do we call a solid liquid or gas that can't be broken into anything else?
Answer:
its called either a physical change or chemical change
Explanation:
2. The most common type of solution is
solution
a
O liquid-solid
O liquid-gas
Which symbol would you likely see if you were using fragile items in the investigation?
electrical hazard
fire hazard
explosive hazard
glass hazard
Answer:
Glass Hazard
Explanation:
How many Oxygen atoms are in two molecules of 2K2CO3 ?
Select the correct answer from the drop-down menu.
Read the excerpt. Then complete the sentence about mood.
The mood of this excerpt can best be described as
.
Why’d you put chemistry as the subject for a question about mood? What’s the excerpt? What’s the choices in the drop down list?
Answer:
mysterious
Explanation:
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