carbon-14 has a half-life of 5,730 years. how long will it take for 112.5 g of a 120.0-g sample to decay radioactively?
Answer:
It will take 22920 years to decay 112.5 g of 120 grams.
Explanation:
The material used as a biological sensor is one dimension of 20 mm, the other Are in nanometers
Answer: 20 , 40
I want know the answer now !
Which of the following is the strongest covalent bond?
Single bond
Double bond
Triple bond
Hydrogen bond
Answer:
Triple bond is the strongest bond
Triple bonds are stronger than the equivalent single bonds or double bonds, with a bond order of three.
Answer:
single bond.In a single covalent bond, when the electrons are shared between two s orbitals, the resulting bond is a sigma (σ) bond . Sigma bonds are the strongest covalent chemical bonds....!!
The density of iron is 7.0 g/cm'. What volume of iron would have a mass of 14.0 g?
Answer:0.284ib/in 3
Explanation:
[tex]\text{Given that,}\\\\\text{Density of iron, }~ \rho = 7 ~\text{g cm}^{-3} = 7 \times 10^{3}~ \text{kg m}^{-3}\\\\\\\text{Mass, m =14 g =} ~ 14 \times 10^{-3} ~\text{kg}\\\\\\\text{Volume of iron,}~ V = \dfrac{m}{\rho} = \dfrac{14 \times 10^{-3}}{7\times 10^{3}} = 2 \times 10^{-6} ~~ m^3[/tex]
now imagine that you have analyzed an additional vntr. from the blot below, what is the expected frequency of occurrence?
The balanced equation shows how sodium chloride reacts with silver nitrate to form sodium nitrate and silver chloride. NaCl AgNO3 Right arrow. NaNO3 AgCl If 4. 00 g of NaCl react with 10. 00 g of AgNO3, what is the excess reactant? AgCl NaCl AgNO3 NaNO3.
The reactant that has been present in excess in the reaction has been NaCl. Thus, option B is correct.
The balanced chemical equation has been:
[tex]\rm NaCl\;+\;AgNO_3\;\rightarrow\;NaNO_3\;+\;3\;AgCl[/tex]
From the balanced equation, for complete utilization of 1 mole of sodium chloride, 1 mole of silver nitrate has been used.
The moles of can be given as:
[tex]\text Moles\;=\;\dfrac{m}{mwt}[/tex]
Where, mass of Silver nitrate, [tex]m=10\;\text g[/tex]
Molecular mass of silver nitrate, [tex]mwt=168\9.87\;\text {g/mol}[/tex]
Substituting the values, moles of silver nitrate has been:
[tex]\rm Moles \;AgNO_3=\dfrac{10}{169.87} \\Moles \;AgNO_3=0.058\;mol[/tex]
Mass of sodium chloride, [tex]m=4\;\text g[/tex]
Molecular mass of sodium chloride, [tex]mwt=58.44\;\text {g/mol}[/tex]
Substituting the values, moles of sodium chloride has been:
[tex]\rm Moles\;NaCl=\dfrac{4}{58.44}\\Moles\;NaCl=0.068\;mol[/tex]
From the balanced chemical equation,
[tex]\rm 1\;moles\;AgNO_3=1\;moles\;NaCl\\0.058\;mol\;AgNO_3=0.058\;mol\;NaCl[/tex]
Since, the available moles of NaCl has been 0.06 mol, and used NaCl has been 0.05 mol. Thus, NaCl has been the excess reactant. Hence, option B is correct.
For more information about the excess reactant, refer to the link:
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Answer:
B- NaCl
Explanation:
if this helped could you put this as the brainiest
1. How many covalent bonds can nitrogen form?
2. Which of the following represents a covalent compound?
A. O2
B. CO2
C. Cl2
D. NaCl
3. 2. Nitrogen is a diatomic element with five valence electrons. Create a model of a molecule of nitrogen.
Answer:
1. 3 covalent bonds
2. CO2
Nitrogen can form three covalent bonds and carbon dioxide represents a covalent compound.Molecule of nitrogen is attached in image below.
What is a covalent bond?Covalent bond is defined as a type of bond which is formed by the mutual sharing of electrons to form electron pairs between the two atoms.These electron pairs are called as bonding pairs or shared pair of electrons.
Due to the sharing of valence electrons , the atoms are able to achieve a stable electronic configuration . Covalent bonding involves many types of interactions like σ bonding,π bonding ,metal-to-metal bonding ,etc.
Sigma bonds are the strongest covalent bonds while the pi bonds are weaker covalent bonds .Covalent bonds are affected by electronegativities of the atoms present in the molecules.Compounds having covalent bonds have lower melting points as compared to those with ionic bonds.
Learn more about covalent bond,here:
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A student creates a hypothesis about their upcoming experiment. What must the
student do in their experiment with relationship to their hypothesis?
create a law based on the hypothesis
change the experiment to make the hypothesis correct
ignore the hypothesis
make observations to prove or disprove the hypothesis
Answer:
D. make observations to prove or disprove the hypothesis
Explanation:
1. Why do you think the map is labeled "Three Sisters”?
also, i know this isn’t chemistry but i couldn’t find Earth Science so don’t come for me . i would appreciate it if y’all could help me the best you can!
Answer:
It's called the “The Three Sisters” because it comes from an Iroquois legend. The Legend says corn, beans and squash are inseparable sisters that were given to the people by the “Great Spirit.” It is important to note, however, that the “Three sisters” are also found in many other areas and tribes around North America.
A sample of ethanol (C2H6O) has a mass of 0. 2301 g. Complete combustion of this sample causes the temperature of a bomb calorimeter to increase by 1. 33°C. The calorimeter has a mass of 2. 000 kg and a specific heat of 2. 45 J/g•°C. What is the heat of combustion for this sample? kJ.
The heat of combustion of the sample is calculated to be -1300 kJmol-1.
We know that energy is neither created nor destroyed but is converted from one form to another. The heat lost by the ethanol when it is burnt is equal to the heat gained by the calorimeter.
Heat gained by calorimeter = 2.×10^3 g × 2. 45 Jg-1°C-1 × 1. 33°C
= 6.5 kJ
Number of moles of ethanol = 0. 2301 g/46 g/mol = 0.005 moles
Heat of combustion of the sample = -( 6.5/0.005 moles) = -1300 kJmol-1
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How many oxygen atoms
in a molecule of table sugar (C12H22011)?
ОА 45
ООО
В. 22
с 12
Op. 11
SUBMIT
Answer:
6.6242 x 10 ^ 24
Explanation:
This is the correct answer because you know there is 11 oxygen moles in 1 mole of sugar so using dimensional analysis you can solve it. You start will 11 moles of oxygen, and multiply by Avogadro's number(6.022 x 10 ^23) to get the amount of atoms. I don't see it as an answer, but I am confident in this, so I would ask your teacher specifically.
Hope this helps!
What does an atom's period tell us?
Select one:
a. Number of protons
b. Number of shells
c. Number of valence
electrons
d. Number of electron
balanced chemical equations a) Sodium + Oxygen
b) Potassium + Chlorine
c) Hydrogen + Chlorine
d) Nitrogen + Hydrogen
e) Calcium + Nitrogen
f) Calcium carbonate
8) Zinc + Hydrochloric acid Zinc chloride + Hydrogen h) Ammonia + Nitrogen - Calcium nitride Carbon dioxide + Calcium oxide Ammonium nitride
Answer:
a) sodium oxide
b) potassium peroxide
c) Hydrogen chloride
d) form ammonia
e) Calcium nitride
Jacinta wrote the following passage about chemical changes.
A chemical change is a change that results in one or more new substances with different properties. When a chemical change occurs, the new substance can give off an odor, such as rotting fruit or cookies baking in the oven. Chemical changes can cause color changes, such as iron rusting and turning a reddish-brown color. When wood is burned or ingredients are mixed for baking a cake, a new substance is made.
Choose the best statement that Jacinta can add to her passage.
Chemical changes, such as rotting fruit and burning wood, are affected by temperature. More heat and energy causes a faster chemical change.
Wood burning and fruit rotting creates new substances through a chemical change that is affected by sound energy.
Rotting fruit and burning wood is a chemical change that occurs because there is a decrease in temperature. Less heat causes a faster chemical change.
When a chemical change occurs, the new substance that is created has properties similar to the original substance.
In the following experiment, a coffee-cup calorimeter containing 100mL OF H2O is used.
Please provide more of the question so I am able to answer, but I do know that H20 has 0 calories.
which statement describes how vapor pressure occurs? (1 point)
a) Some molecules of a substance have high enough kinetic energy to vaporize. These molecules exert
pressure on the substance.
b) Some molecules of a substance have low enough kinetic energy to melt. These molecules exert pressure on the substance
c) Some molecules of a substance have low enough kinetic energy to vaporize. These molecules exert
pressure on the substance.
d) Some molecules of a substance have high enough kinetic energy to melt. These molecules exert pressure on the substance
Some molecules in a substance have a high kinetic energy hence they are able to convert into vapor. These molecules exert pressure on the liquid surface.
We know that the molecules that compose matter are in constant random motion. The kinetic energy of all the molecules in the liquid are not the same. The molecules at the surface of the liquid posses more kinetic energy than the molecules below.
Some molecules of a substance have high enough kinetic energy to vaporize. These molecules exert pressure on the substance.
Learn more: https://brainly.com/question/25273232
Answer:
Some molecules of a substance have high enough kinetic energy to vaporize. These molecules exert pressure on the substance.
Explanation:
How many moles of nitrogen dioxide, NO2, are present if the reaction conditions are 330 K, 2.46 atm, and 4.8 L
There are 0.436 moles of nitrogen dioxide, NO2, present if the reaction conditions are 330 K, 2.46 atm, and 4.8 L.
IDEAL GAS LAW:The number of moles of nitrogen dioxide (NO2) in this question can be calculated by using the ideal gas law equation as follows:
PV = nRT
Where;
P = pressure (atm)V = volume (L)T = temperature (K)R = gas law constant (0.0821 Latm/molK)n = number of molesAccording to the reaction conditions given in this question;
P = 2.46 atmV = 4.8Ln = ?T = 330K2.46 × 4.8 = n × 0.0821 × 330
11.81 = 27.093n
n = 11.81 ÷ 27.093
n = 0.436mol
Therefore, there are 0.436 moles of nitrogen dioxide, NO2, present if the reaction conditions are 330 K, 2.46 atm, and 4.8 L.
Learn more about the ideal gas law at: https://brainly.com/question/4147359?referrer=searchResults
This chemical equation is balanced.
F2 + 2NaBr
2NaF + Br2
How does the balanced chemical equation show the conservation of matter
in this chemical reaction?
A. There are fewer Na atoms in the reactants than in the products.
B. The number of Fatoms in the reactants equals the number of F
atoms in the products.
C. The compound NaF is a substance that is different from the
compound NaBr.
D. There are more Br atoms in the reactants than in the products.
1. While on a movie set, a stuntman jumps off
the roof of a building. As he falls toward an
airbag, what is increasing?
A. gravity
B. wind velocity
C. kinetic energy
D. potential energy
kinetic energy kkkkkkkkkk
In the first half of the citric acid cycle, ____________ is oxidized, yielding a pair of electrons that reduce a molecule of NAD to NADH.
Answer:
isocitrate
Explanation:
how many molecules are in 122 grams of Cu(NO3)2
Answer:
3.917 x 10 ^ 23
Explanation:
You just want to use dimensional analysis to solve. So first start with 122g of copper(II) nitrite, and divide by the molecular weight to get it into moles. Then you know that 1 mole = 6.022 x 10 ^23 molecules (Avogadro's Number) so multiply that by your current moles. A hint for these problems always convert what you were given to moles since it is easy to get to a lot of things through them. ** Use the molar mass/molecular weight for going from grams to moles or moles to grams and use Avogadro's number when going from moles to atoms/molecules or reverse.
Hope this helps!
Select the correct answer.
Tropical forests contain dense trees, which allow less sunlight to penetrate. Emergent trees are trees that grow to a height of more than 45 to 55 meters, above the usual height of trees in tropical forests. Which system provides the best possible explanation for why these trees grow to those heights?
A.
shunted growth pattern
B.
homeostasis
C.
due to less exposure to sunlight
D.
phototropism
Did the flower used in this investigation come from a plant that reproduces sexually or asexually? Explain your answer. (If u don’t know the answer don’t answer.) (No picture) (I didn’t know what category)
Answer:
Asexually
Explanation:
Plant's cannot reproduce sexually
ow does the food chain start? A Plant life uses energy from the sun to make food. B Insects like grasshoppers eat plant life. C Animals like rats eat insects. D Humans eat large animals and plant life
HELLLPPPP ASAP !!!! Pls
Answer:
Melting point, boiling point, state of matter at room temperature, heat of vaporization, flammability and reactivity
Explanation:
The pH scale is used to tell if a substance
is an acid or base. Substances with a pH
of 7 are neutral. An acid is anything
below 7 and a base is anything above
7.What would a household cleaner with a
pH of 10 be considered on the pH scale?
Answer:
Explanation:
pH > 7 as 10 is more than 7
The cleaner is very corrosive.
It is a moderately basic. If it was 12 that would make it much more basic (100 times more basic).
In Natural selection, who/what makes the decision about which traits are desirable and get passed to future generations?
please need help asap thank you.
Answer:
Different alleles and genes determine what gets passed down.
Explanation:
Its a pretty weird/ open ended question, but the alleles that help an organism survive, will be passed down more often because they are more "fit" and can out survive its competitors within a certain species.
7. Describe the difference between a genetically modified organism (GMO) and an unmodified organism.
Answer:
there
Explanation:
organic food is farmed and manufactured per the guidelines put forth by the Department of Agriculture. Organic food is typically pesticide-free, GMO-free, and sustainably farmed.
Non-GMO food, or non-genetically modified food, has not been altered or engineered in any way. Non-GMO food doesn’t necessarily adhere to the same guidelines that organic food does.
GMO food has been genetically modified in some form, usually in a laboratory.
7) Element Families on the Periodic Table have similar _____________________. There are ________ Families.
8) Alkali Metals are good conductors of _____________________________ and ________________________________.
9) There are a total of _________ elements that are grouped as Transition Metals.
10) As opposed to metals, non-metals can be very __________________________. They have no metallic ____________
and do not reflect ______________________.
11) All Lanthanide Series elements occur naturally except for ___________________________________.
12) All Actinide Series elements are ___________________________ and most are _____________________
The periodic table is composed of metals and nonmetals arranged in groups and periods.
The periodic table is an arrangement of elements in groups and periods based on their properties. The properties of elements repeat at regular intervals hence the term, "periodic".
The answers to the questions are;
7) Element Families on the Periodic Table have similar properties. There are 18 families.
8) Alkali Metals are good conductors of heat and electricity.
9) There are a total of 38 elements that are grouped as Transition Metals.
10) As opposed to metals, non-metals can be very opaque. They have no metallic luster and do not reflect light.
11) All Lanthanide Series elements occur naturally except for promethium.
12) All Actinide Series elements are radioactive and most are synthetic.
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which colour would you expect ekasilicon to be
Answer:
it would ether be gray to black or silver to gray and black
Explanation:
because of my calculation ekasillicon would be that color because of the eyes and because of your color seeing .