6.)Isotopy is a phenomenon whereby atoms of an element exhibit different mass numbers but have the same atomic number. Ion is any atom or group of atoms which possesses an electric charge.
8.) Acid is a substance which produces hydrogen ions (or protons) as the only positive ion when dissolved in water.Base is a substance which will will neutralize an acid to yield a salt and water only.
7.) Valency is the combining power of an element or radical.It is actually the oxidation number assigned to the element or group of elements.
5.) Atomic shells are K,L,M,N.The electrons are negatively charged and revolve around the nucleus in spherical regions called shells or energy levels.
9.) Families of Element:Group 1 &2 make up the s-block.Group 3 to 7 and 0 form the p-block.The transition elements occurs between Groups 2 and 3 in the periodic table.They form the d-block because they contain d electrons in addition to the s and p electron.The lanthanides and actinides also occurs between group 2 and 3 in periods 6 and 7 respectively. They form the f-block because they contain f electrons in addition to the s,p and d electrons.
I hope this helps.....
A 1.000 g sample of nitrogen combined with a 0.0720 g sample of hydrogen to form N2H2. What compound is formed if 1.000 g of nitrogen combines with 0.2160 g of hydrogen?
N2H6 NH3 NH4+ N4H4
Answer:
N₂H₆
Explanation:
A 1.000 g sample of nitrogen combined with a 0.0720 g sample of hydrogen to form N₂H₂ .
1.000 g of nitrogen combines with 0.2160 g of hydrogen in the next compound .
In this compound the component of nitrogen remains the same but the component of hydrogen becomes .2160 / .0720 = 3 times .
Hence component of hydrogen in the new compound will change from
H2 to H6 .
Hence the chemical formula of new compound will be
N₂H₆ .
So our professor didn't go over this but is freshly cut sodium, but rapidly tarnishes on contact with air a physical or chemical property?
Answer:
Hey!
After the slight confusion (haha)...
Your answer should be a CHEMICAL CHANGE / PROPERTY
Explanation:
Its CHEMICAL because the sodium has reacted with the air (oxygen in technical terms) which then forms SODIUM OXIDE...the tarnishing of the cut sodium surface it a thin layer of the SODIUM OXIDE...
HOPE THIS HELPED!
How does the amount of sunlight affect the number of eggs laid by a chicken?
Explanation:
The amount of daylight hours affects a chicken's reproductive cycle. Hens will begin laying when the amount of daylight reaches 14 hours per day during early spring. Maximum egg laying will occur when the day length reaches 16 hours per day
The composition of a liquid-phase reaction 2A - B was monitored spectrophotometrically. The following data was obtained: t/min 0 10 20 30 40 conc B/(mol/L) 0 0.089 0.153 0.200 0.230 0.312
1) Determine the order of the reaction. (6 pts.)
2) Find its rate constant. 19 pts.) Note: no unit is needed, just the numerical answer. Hint: convert your minutes to seconds.
Answer:
1) The order of the reaction is of FIRST ORDER
2) Rate constant k = 5.667 × 10 ⁻⁴
Explanation:
From the given information:
The composition of a liquid-phase reaction 2A - B was monitored spectrophotometrically.
liquid-phase reaction 2A - B signifies that the reaction is of FIRST ORDER where the rate of this reaction is directly proportional to the concentration of A.
The following data was obtained:
t/min 0 10 20 30 40 ∞
conc B/(mol/L) 0 0.089 0.153 0.200 0.230 0.312
For a first order reaction:
[tex]K = \dfrac{1}{t} \ In ( \dfrac{C_{\infty} - C_o}{C_{\infty} - C_t})[/tex]
where :
K = proportionality constant or the rate constant for the specific reaction rate
t = time of reaction
[tex]C_o[/tex] = initial concentration at time t
[tex]C _{\infty}[/tex] = final concentration at time t
[tex]C_t[/tex] = concentration at time t
To start with the value of t when t = 10 mins
[tex]K_1 = \dfrac{1}{10} \ In ( \dfrac{0.312 - 0}{0.312 - 0.089})[/tex]
[tex]K_1 = \dfrac{1}{10} \ In ( \dfrac{0.312 }{0.223})[/tex]
[tex]K_1 =0.03358 \ min^{-1}[/tex]
[tex]K_1 \simeq 0.034 \ min^{-1}[/tex]
When t = 20
[tex]K_2= \dfrac{1}{20} \ In ( \dfrac{0.312 - 0}{0.312 - 0.153})[/tex]
[tex]K_2= 0.05 \times \ In ( 1.9623)[/tex]
[tex]K_2=0.03371 \ min^{-1}[/tex]
[tex]K_2 \simeq 0.034 \ min^{-1}[/tex]
When t = 30
[tex]K_3= \dfrac{1}{30} \ In ( \dfrac{0.312 - 0}{0.312 - 0.200})[/tex]
[tex]K_3= 0.0333 \times \ In ( \dfrac{0.312}{0.112})[/tex]
[tex]K_3= 0.0333 \times \ 1.0245[/tex]
[tex]K_3 = 0.03412 \ min^{-1}[/tex]
[tex]K_3 = 0.034 \ min^{-1}[/tex]
When t = 40
[tex]K_4= \dfrac{1}{40} \ In ( \dfrac{0.312 - 0}{0.312 - 0.230})[/tex]
[tex]K_4=0.025 \times \ In ( \dfrac{0.312}{0.082})[/tex]
[tex]K_4=0.025 \times \ In ( 3.8048)[/tex]
[tex]K_4=0.03340 \ min^{-1}[/tex]
We can see that at the different time rates, the rate constant of [tex]k_1, k_2, k_3, and k_4[/tex] all have similar constant values
As such :
Rate constant k = 0.034 min⁻¹
Converting it to seconds ; we have :
60 seconds = 1 min
∴
0.034 min⁻¹ =(0.034/60) seconds
= 5.667 × 10 ⁻⁴ seconds
Rate constant k = 5.667 × 10 ⁻⁴
Adding charts and graphs helps a scientist
O To state the problem
O To determine trends
O To simplify results
O Both B and C
O All of the above
Answer:
b and c
Explanation:
the problem was solved through the experiment and tested
2The higher the numbers on the NFPA diamond, the more _____ the substance is.
ARare incorrect answer
BDangerous incorrect answer
CPure incorrect answer
DSafe
The correct answer is B. Dangerous
Explanation:
The NFPA diamond is used to show how safe or dangerous a substance or material is based on four main categories: Health (blue), Flammability (red), Instability (yellow), special hazards (white). Moreover, the three first hazards are expressed using numbers from 0 to 4, in which 0 means no hazard while 4 is the most dangerous category. For example, in the health square finding 0 means the substance represents no hazard for health, while 4 means the substance is lethal. This means the higher the number in this diamond, the most dangerous the substance is.
Some people argue that a policy of putting out wildfires is having a negative long-term effect on the number and strength of wildfires. Suggest why this could be the case.
Answer:
The reason for this is that putting out the fires only postpones the fire outbreak to a later date, and there is the fear of the fire outbreak being more sever when it actually comes.
When wildfires burn, they clean up the forest off dead trees and falling logs. Also dried leaves and twigs and unnecessarily dense vegetation is cleared up by the fire. These materials are the main fuel of these wildfires. Putting out these fires, especially those that start naturally means that these fuel that should be cleaned up are allowed to accumulate so that when the fire actually happens, it does so with an unnatural intensity. Also, when fire burns, the ashes that are left act as nutrition for the forest, and the forest is allowed to regrow; reborn from the ashes. The only cases that might need human intervention is when the fire is human caused or due to human activities. Natural causes of fire can be due to a very high temperature, lightning striking a tree, etc.
How many mL are in 1.000 cup?
Answer:
236588
Explanation:
1000 x 237 for an approx. amount
Answer:
236.588 mL in 1 cup.
Explanation:
For this problem, you must know that 1 cup is equal to 8 ounces and that 1 ounce is 29.5735 mL. Using this information, let' perform the conversion.
1 cup * ( 8 oz / 1 cup ) * ( 29.5735 mL / 1 oz) == ? mL
( 1 cup * 8 oz * 29.5735 mL ) / ( 1 cup * 1 oz) == ? mL
236.588 mL == ? mL
Hence, there are 236.588 mL in 1 cup.
Cheers.
is another way in which nitrogen gets fixed in the soil
Answer:
through Rhizobium bacteria
A 1.75 gram perfect cube of wood has a side measure of 2.45 cm, what is the density of the wood?
Answer:
0.119 g/cm³
Explanation:
Step 1: Given data
Mass of the cube (m): 1.75 g
Side measure (l): 2.45 cm
Step 2: Calculate the volume of the cube
We will use the following expression.
V = l³
V = (2.45 cm)³
V = 14.7 cm³
Step 3: Calculate the density (ρ) of the cube
The density of the cube is equal to its mass divided by its volume.
ρ = m/V
ρ = 1.75 g/14.7 cm³
ρ = 0.119 g/cm³
Show the difference in the reactivity of Na,Ca,Mg,Al,Fe,Cu with H2O
Answer:
Explanation:
Na react with H2O to form NAOH
2 Na+2H2O....................2NAOH + H2
Ca react with water and form calcium hydroxide
Ca + 2H2O........................Ca(OH)2
Mg react with water and form Magnesium hydroxide
Mg +2H2O .........................Mg(OH)2 however this coating of mg(oh)2 prevent it from further reaction
Fe react with water and form ferric hydride
3Fe +H2O.......................2 FeH +FeO
copper do not react with water
At STP how many liters of NH3 can be produced from the reaction of 2.00 mol of N2 with 2.00 mol of H2
Answer:
29.9L of NH₃ are produced
Explanation:
The reaction of H2 with N2 to produce NH3 is:
3 H2 + N2 → 2 NH3
For a complete reaction of 2.00 moles of H2 there are required:
2.00 moles H2 * (1 mole N2 / 3.00 moles H2) = 0.667 moles N2
The limiting reactant is hydrogen.
The volume of hydrogen using PV = nRT is (STP: 273.15K; 1atm):
V = nRT / P
V = 2.00mol * 0.082atmL/molK*273.15K / 1atm
V = 44.8L
As we know for the reaction, 3 moles of hydrogen produce 2 moles of NH3.
The moles of H2 produced are:
2mol H2* (2mol NH3 / 3mol H2) = 1.33 moles NH3 are produced
Under pressure and temperature constant (STP) you can apply The Avogadro's law that states:
V₁ / n₁ = V₂ / n₂
Where V is volume and n moles of 1, the first gas and 2, the second gas.
V₁ / n₁ = V₂ / n₂
44.8L / 2.00mol = V₂ / 1.33 moles
V₂ =
29.9L of NH₃ are produced
When dipentyl ether is treated with HI, what type of reaction occurs? both SN1 and SN2 SN2 E1 SN1 E2
Answer:
SN2
Explanation:
The first step of ether cleavage is the protonation of the ether since ROH is a better leaving group than RO-.
The second step of the reaction may proceed by either SN1 or SN2 mechanism depending on the structure of the ether. Methyl and primary ethers react with HI by SN2 mechanism while tertiary ethers react with HI by SN1 mechanism. Secondary ethers react with HI by a mixture of both mechanisms.
Dipentyl ether is a primary ether hence when treated with HI, the reaction with HI proceeds by SN2 mechanism as explained above.
Which of the following correctly describes a mixture? (4 points) a The particles are chemically bonded together, and they retain their individual physical and chemical properties. b The particles are not chemically bonded, and they can only combine in certain set ratios. c The particles do not retain their individual chemical properties, and they can only be separated by chemical means. d The particles have no set ratio for how to combine, and they can be separated by physical means.
Answer:
the answer is B the particles are not chemically bonded, they can only be combined in a certain set ratios
Explanation:
20g of ideal gas contains only atoms of s and o occupies 5.6l at ntp what is the mol wt of gas
Answer:
20g gas contains and this so allow in tha 36G in per laar
Explanation:
Write the numbers in scientific notation.
291.7 = 2.917
X10%
where x =
0.0960 -
X10%
where x =
The numbers in scientific notation are 291.7 = 2.917 × 10₂ and 0.0960 = 9.60 × 10⁻².
Scientific notation is commonly used in scientific and mathematical calculations, as well as when dealing with very large or very small numbers. It allows for a more compact and manageable representation of these numbers.
To write the numbers in scientific notation, we need to express them in the form of "a × 10^b," where "a" is a number between 1 and 10, and "b" is an integer.
For the number 291.7, write it in scientific notation as:
291.7 = 2.917 × 10²
For the number 0.0960, write it in scientific notation as:
0.0960 = 9.60 × 10⁻²
To learn more about scientific notation, follow the link:
https://brainly.com/question/19625319
#SPJ6
John had seen people sprinkle salt on ice in the winter. The salt appeared to melt the ice. He decided to sprinkle salt on a larger block of ice. Then he added food coloring so he better could see the results. How did creativity help John in this experiment? A. It helped him use materials in a new way to help him gather data. B. It helped him reason through the results of his experiments. C. It helped him follow the steps of the procedure precisely. D. It helped him remember something from his past.
The correct answer is A. It helped him use materials in a new way to help him gather data.
Explanation:
The use of food coloring in this experiment makes it easier to observe how salt affects ice and if this helps ice to melt. This implies by adding food coloring John can better observe the phenomenon he is studying and gather precisely data about this phenomenon, which would also help him to draw accurate conclusions. In this context, the use of food coloring shows creativity because he is using this material as an alternative way and this use would help him in the stage of gathering data (option A), which is the stage that follows after implementing experiments.
Answer:
A
Explanation:
Just got it right on my quiz!! I hope this helps! <3
Please Help Me Which ink spot had the most pigments? Question 3 options: A) red B) blue C) black D) green
Answer:
Black
Explanation:
Two atoms of hydrogen combine to form a molecule
of hydrogen gas, the energy of the H2 molecule is :
(1) Greater than that of seperate atoms
(2) Equal to that of seperate atoms
(3) Lower than that of seperate atoms
(4) Some times lower and some times higher
Answer:
lower than the separate atoms. Because an electron in this molecular orbital is strongly attracted to both nuclei, the electron is more stable (at lower energy) than it is in the 1s orbital of the hydrogen atom. Because it concentrates electron density between the nuclei, the bonding molecular orbital holds the atoms together in a covalent bond.
g The large negative free energy of hydrolysis of Phosphoenolpyruvate is largely due to _______________ of the enol pyruvate.
Answer:
hello your question lacks some parts below are the missing option
A. hydrophobic interaction
B. nucleophilic attack
C. tautomerization
D. resonance
answer : Tautomerization ( C )
Explanation:
The large negative free energy of hydrolysis of Phosphoenolpyruvate is largely due to tautomerization of the enol pyruvate. tautomerism of enol takes place by transferring proton from in an intramolecular way.
one of the most common tautomerism is keto-enol which makes uses of either an acid or base as a catalyst
A block of aluminum occupies a volume of 0.015 L and has a mass of 40.5 g. What is its density
Answer:
Density = 2700 g/LExplanation:
Density of a substance can be found by using the formula
[tex]Density = \frac{mass}{volume} [/tex]
From the question
volume = 0.015 L
mass = 40.5 g
Substitute the values into the above formula and solve for the Density
That's
[tex]Density = \frac{40.5}{0.015} [/tex]
We have the final answer as
Density = 2700 g/L
Hope this helps you
Cell membranes are largely hydrophobic structures. Which compound will pass through a membrane more easily, glucose or 2,4-dinitrophenol? Explain.
Answer:
2,4-dinitrophenol
Explanation:
A hydrophobic molecule does not dissolve nor mix with water. The cell membranes are made up of hydrophobic lipids. Hence, hydrophobic molecules easily pass through the cell membrane.
Glucose is partly hydrophilic hence it is transported across the cell membrane by special proteins. However, 2,4-dinitrophenol is a hydrophobic molecule thus it is easily transported across the cell membrane.
Calculate the density of an object with a mass of 220 and a volume of 145mL.
Answer:
1.52 g/mL
Explanation:
The formula for finding the density of an object is d = m/v, or density = mass divided by volume.
Therefore, we can input the two values and solve for d.
d = 220/145
d = 44/29
d ≈ 1.52 g/mL
A sample of mass 6.814 grams is added to another sample weighing 0.08753 grams.
The subsequent mixture is then divided into exactly 3 equal parts. One of those parts has the yield multiplied by 7.6335 times; what is the final mass?
Answer:
17.5609g
Explanation:
According to the question, a sample of mass 6.814 grams is added to another sample weighing 0.08753 grams. That is weight of sample 1 + weight of sample 2;
6.814 + 0.08753 = 6.90153grams
Next, the subsequent mixture is then divided into exactly 3 equal parts i.e. 6.90153grams divided by 3
= 6.90153/3
= 2.30051grams.
One of the equal parts is 2.30051grams, which is then multiplied by 7.6335 times I.e. 2.30051 × 7.6335 = 17.5609grams
Therefore, the final mass is 17.5609grams
A flask that weighs 345.8g is filled with 225mL of carbon tetrachloride. The weight of the flask and carbon tetrachloride is found to be 703.55g. From this information, calculate the density of carbon tetrachloride.
Answer:
Density = 1.59 g/mLExplanation:
The density of carbon tetrachloride can be found by using the formula
[tex]Density = \frac{mass}{volume} [/tex]From the question
Volume = 225 mL
To find the mass of carbon tetrachloride in the flask subtract the mass of the flask from the total mass of the flask and carbon tetrachloride
That's
mass of carbon tetrachloride =
703.55 - 345.8
= 357.75 g
Substitute the values into the above formula and solve for the density
That's
[tex]Density = \frac{357.75}{225} [/tex]We have the final answer as.
Density = 1.59 g/mL
Hope this helps you
Which statement best describes the types and locations of particles that make up the atom? A. The neutral-charged neutrons and positive-charged protons are found within the nucleus, and the negative-charged electrons orbit outside the nucleus of the atom. B. The neutral-charged neutrons, positive-charged protons, and negative-charged electrons are all found within the nucleus of the atom. C. The negative-charged electrons and positive-charged protons are found within the nucleus, and the neutral-charged neutrons orbit outside the nucleus of the atom. D. The negative-charged neutrons and positive-charged protons are found within the nucleus, and the neutral-charged electrons orbit outside the nucleus of the atom.
Answer:
A. The neutral-charged neutrons and positive-charged protons are found within the nucleus, and the negative-charged electrons orbit outside the nucleus of the atom.
Explanation:
An atom basically consists of three sub atomic particles. They are; Neutrons, Electrons and Protons.
The Electrons are negatively charged and can be found outside the nucleus of the atom,
The Protons are positively charged and can be found in the nucleus of an atom.
The Neutrons are neutral in terms of charged and can be found in the nucleus along with the protons.
The option that is correct is;
A. The neutral-charged neutrons and positive-charged protons are found within the nucleus, and the negative-charged electrons orbit outside the nucleus of the atom.
A solution is prepared at that is initially in benzoic acid , a weak acid with , and in sodium benzoate . Calculate the pH of the solution. Round your answer to decimal places.
Answer:
[tex]pH=4.1[/tex]
Explanation:
Hello,
In this case, for a concentration of 0.42 M of benzoic acid whose Ka is 6.3x10⁻⁵ in 0.33 M sodium benzoate, we use the Henderson-Hasselbach equation to compute the required pH:
[tex]pH=pKa+log(\frac{[base]}{[acid]} )[/tex]
Whereas the concentration of the base is 0.33 M and the concentration of the acid is 0.42 M, thereby, we obtain:
[tex]pH=-log(Ka)+log(\frac{[base]}{[acid]} )\\\\pH=-log(6.3x10^{-5})+log(\frac{0.33M}{0.42M} )\\\\pH=4.1[/tex]
Regards.
sort the sequences based on the types of mutation they display
Answer:
There are three types of DNA Mutations: base substitutions, deletions and insertions. Single base substitutions are called point mutations, recall the point mutation Glu -----> Val which causes sickle-cell disease. Point mutations are the most common type of mutation and there are two types.
classify the organisms based on what they eat. producer consumer decomposer
Lowest - Producer - plants (mostly)
They get food by converting sunlight into nutrients
Middle - Consumer - example animals
They eat other living things such as plants or other animals for their nutrients
Top - Decomposer - bacteria/microorganisms
They decompose dead body
sorry if im wrong
Johnny was finished with his
experiment so he placed all of his
unused chemicals back into their
original containers. What should
Johnny have done instead?
The sono