Answer:
A group is a column of elements in the periodic table of the chemical elements.
So, the columns on the periodic table are called groups.
What type of change occurs during a chemical reaction?
Answer:
physical change.
Explanation:
because it changes its physical attributes
What is a limiting factor?
A limiting factor determines where an organism can live.
O A limiting factor helps an organism outcompete other organisms.
O A limiting factor helps an organism survive in a habitat.
PLEASE QUICKLY. I'll give BRAINLIEST. A sample contains 25% parent isotope and 75% daughter isotopes. If the half-life of the parent isotope is 72 years, how old is the sample?
144 years old
216 years old
288 years old
360 years old
From the calculations and the principles of radioactivity, the age of the parent isotope is 144 years
What is radioactivity?The term radioactivity has to do with the spontaneous decay of a substance.
We know that we have about 25% parent isotope still remaining hence;
[tex]0.693/t1/2 =2.303/t log No/N\\When N =0.25 No and t1/2 = 72 years\\0.693/72 =2.303/t log No/0.25No\\0.0096 = 2.303/t *0.60206\\0.0096 = 1.3865/t\\t = 1.3865/0.0096\\t =144 years[/tex]
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Answer:
A. 144 years old
Explanation:
How are people responsible for marine debris
Answer:
Marine debris comes from many different sources and enters the ocean in many ways. Intentional littering and dumping are a big cause of marine debris. ... Those rivers and streams can eventually carry the trash to the ocean. Improper or careless waste disposal is another big cause.
hope this helps
have a good day :)
Explanation:
How many formula units are there in 14.50 moles of any compound?
___X 10^___formula units
Answer:
8.73 × 10²⁴ formula units
Explanation:
To calculate the number of formula units a substance contain, we multiply the number of moles by Avagadro number (6.02 × 10²³)
number of formula units = 14.50 moles × 6.02 × 10²³
= 87.29 × 10²³
= 8.73 × 10²⁴ formula units.
In your OWN words, what is the difference between a solute, solvent, and solution?
Answer:A solution is a homogeneous mixture consisting of a solute dissolved into a solvent . The solute is the substance that is being dissolved, while the solvent is the dissolving medium.
Explanation:A solution is a homogeneous mixture consisting of a solute dissolved into a solvent . The solute is the substance that is being dissolved, while the solvent is the dissolving medium.
PLEASEEEEE CAN SOMEONE HELP MEEE??? (iI have TWO questions PLSPLSPLSPSLPLSPLSPLSP)
3.) What happened to Patroclus at the end of yesterday's reading?
He won the battle.
He went to Mt. Olympus to talk to Zeus.
He died.
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4.Who was Agamemnon trying to persuade to come fight with him again?
Patroclus
Achilles
Odysseus
Hector
What volume of 2M NaOH is required to completely neutralize 25mL of 1M HCl?
Answer:
[tex]\boxed {\boxed {\sf 12.5 \ mL \ NaOH}}[/tex]
Explanation:
In a neutralization reaction, an acid and base react to form salt and water. The hydrogen ions (H+) and hydroxide ions (OH-) combine to form water, while the other spectator ions bond to make salt.
For this reaction, the acid is HCl (hydrochloric acid) and NaOH (sodium hydroxide).
The H (from HCl) and OH (from NaOH) combine to make water (HOH or H₂O). The other ions, Cl and Na combine to form NaCl or sodium chloride. Let's write the neutralization reaction.
[tex]HCl _{(aq)}+NaOH _{(aq)} \rightarrow NaCl _{(aq)} + H_2O _{(l)}[/tex]
Now let's perform the calculation. We should use the titration equation or:
[tex]M_AV_A= M_BV_B[/tex]
where M is the molarity of the acid or base and V is the volume.
We know there are 25 milliliters of 1 molar HCl (acid) and an unknown volume of 2 molar NaOH (base).
[tex]\bullet M_A= 1 \ M \\\bullet V_A= 25 \ mL \\\bullet M_B= 2 \ M[/tex]
Substitute the known values into the formula.
[tex]1 \ M * 25 \ mL = 2 \ M * V_B[/tex]
Since we are solving for the volume of the base, we must isolate the variabel. it is being multiplied by 2 M and the inverse of multiplication is division. Divide both sides by 2 M.
[tex]\frac { 1 \ M * 25 \ mL}{2 \ M }=\frac{2 \ M * V_B}{2 \ M}[/tex]
[tex]\frac { 1 \ M * 25 \ mL}{2 \ M }= V_B[/tex]
The units of M cancel.
[tex]\frac { 1 * 25 \ mL}{2 }=V_B[/tex]
[tex]\frac {25}{2} \ mL= V_B[/tex]
[tex]12.5 \ mL= V_B[/tex]
12.5 milliliters of 2 M sodium hydroxide are required to neutralize 25 mL of 1 M hydrochloric acid.
Which element has 16 neutrons, 15 protons, and 15 electrons?
Answer:
phosphorus
Explanation:
Answer:
phosphorus
Explanation:
phosphorus has to lose electrons
What is the formula for percent by mass in chem
Answer:
mass percent = (mass of solute / mass of solution) x 100%
Explanation:
Which statement about pollination is
TRUE?
Flowers are always pollinated
by insects.
Pollen is always transferred
from the same flower
When pollination occurs.
pollen sticks to the anther.
When pollination occurs
pollen sticks to the stigma.
Answer:
D; the pollen sticks to the stigma
Explanation:
When a flower is pollinated, the pollen sticks to the stigma. However, it is not always pollinated by insects (birds and other factors can as well), pollen can be transferred from different flowers (as long as they're the same species) and pollination doesn't stick to the anther.
Answer:
d
Explanation:
because when pollution occurs than the insects move to the flower to sick nectar and then pollan giains stuck in the insect body
As Earth's population continues to grow, so will the competition for our water supply. Describe three actions that our government could take to reduce competition for water use.
Answer:
Recycling waste water, awareness about efficient use of water and rain water harvesting.
Explanation:
Our government could take to reduce competition for water use by recycling waste water, awareness about efficient use of water and rain water harvesting are the methods which can reduce competition for water supply. Awareness in people about water bring great change and the people used water efficiently. Water should be harvested through making of reservoirs which collects water from rain which can be used for drinking as well as washing purpose. Recycling of waste water also increases the amount of water and reduce competition.
¿en que estado de agregacion se encuentra un cuerpo con forma y volumen propio?
Answer: Um what is it?
Explanation:
Para este mismo ejercicio, si se administran 2.5 litros de está solución (2,500ml) en un intervalo de 24 horas que cantidad en gramos de paciente en un día?
Answer:
Se administran 2500 gramos de solución por día.
Explanation:
Dado
Volumen de la solución = 2,5 litros
Como sabemos 1 litro = 1000 gramos
Por lo tanto, 2.5 litros = 2500 gramos
Se administran 2,5 litros en un intervalo de 24 horas o 1 día.
De ahí que se pueda decir que se administran 2500 gramos de solución al día.
HELP PLEASEWhat is the molarity of 4.0 moles of sodium chloride (NaCl) in 125 mL of solution?
Hint: 1 L of solution = 1000 mL of solution
Question 19 options:
500 M
32 M
0.50 M.
0.032 M
A sample of unknown gas in a closed container has a temperature of 37oC and a pressure of 2 atm. What will be the pressure if the sample is heated to 127oC?
note: Put your answer up to 1 decimal and the unit, in the blank
Answer:
hdfcghbjhaiedg
Explanation:
Convert 3.01×10 23 molecules of H2O to moles.
A cat gets squirted with a water gun after peeing on the carpet. After a few weeks, the no longer pees on the
carpet. This is an example of...
An instinct
An individual adapting due to memories formed from experiences with stimuli
A species adapting due to a genetic mutation
An individual adapting due to a genetic mutation
Answer:
An individual adapting due to memories formed from experiences with stimuli
Explanation:
How can I solve this pls
Explanation:
A= Mercury (ll) oxide
B= Mercury and Oxygen
This is an oxidation-reduction (redox) reaction:
2 HgII + 4 e- → 2 Hg0
(reduction)
2 O-II - 4 e- → 2 O0
(oxidation)
HgO is an oxidizing agent, HgO is a reducing agent.
Which of the following represents an endothermic reaction?
Question 12 options:
A + B --> C + D + Heat
heat pack getting hot
Heat + A + B --> C + D
burning wood
Answer:
ANSWERThe second one would be one of the application of an endothermic reaction as because endothermic reaction always have the heat in the process to mix the reactants and form the products as here in a burning wood when the wood is supplied with heat then it change into products as ashes and smoke fumes So here due to the heat is involved to form the products thats the reaction is endothermic reaction.
Hope it helps
A flexible camping tank has a sample of butane gas at 17.2 atm and has volume of 6.5L. What will be the volume if the pressure is adjusted to
6.4 atm?
Answer:
If the pressure is adjusted to 6.4 atm, the volume will be 17.47 atm.
Explanation:
Boyle's law says that the volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure. That is, if the pressure increases, the volume decreases while if the pressure decreases, the volume increases.
Mathematically, Boyle's law indicates that the product of pressure and volume always has the same value:
P*V= k
Analyzing an initial state 1 and a final state 2, it is satisfied:
P1*V1= P2*V2
In this case:
P1= 17.2 atmV1= 6.5 LP2= 6.4 atmV2= ?Replacing:
17.2 atm* 6.5 L= 6.4 atm* V2
Solving:
[tex]V2=\frac{17.2atm*6.5 L}{6.4 atm}[/tex]
V2=17.47 L
If the pressure is adjusted to 6.4 atm, the volume will be 17.47 atm.
2.An atom with 35 mass number has 17
proton in its nucleus. Find the number of
neutron. What is its atomic number?
Answer:
mass no = A
Atomic number = Z= no of protons
Neutron = n
n = A-Z
n= 35- 17
= 18
Explanation:
A block of aluminum weighing 200 g is cooled from 100C to 50°C with the release of 1080 joules of heat. From this data, calculate the specific heat of aluminum.
Answer:
0.108
Explanation:
You use the formula Q =mco
M is mass
Q is th heat release
C is specific heat
O is the temperature change
Substitute what you have and what you get in the information in the equation then you will get your answers
Which of the following has the greatest effect on colligative properties?
A. Calcium chloride (CaCl2)
B. Aluminum Nitrate (Al(NO3)3)
C. Epsom salt (MgSO4)
D. Sodium chloride (NaCl)
Which of the following steps correctly converts 3 moles of fluorine to an equivalent number of particles of fluorine?
Group of answer choices
Divide Avogadro's number by 3.
Multiply 3 by Avogadro's number.
Multiply 3 by the atomic mass of fluorine.
Divide the atomic mass of fluorine by 3.
Answer:
B) Multiply 3 by Avogadro's number
Explanation:
This is according to Study.com
3 moles of fluorine contains 18.066✖10²³ Particles. thus, option B is correct
How many are there no. of particles in 1mole?One mole contains 6.022✖10²³ particles.
3 moles of flourine contains 3✖6.022✖10²³ particles
Hence, option “B” is correct
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Calculate the current in amperes required to produce 18.0g of aluminium in 1.50hrs (al=27.og )
Answer:
35.7 A
Explanation:
Let's consider the reduction half-reaction of Al³⁺.
Al³⁺ + 3 e⁻ ⇒ Al
We will calculate the charge required to produce 18.0 g of Al using the following conversion factors.
1 mole of Al has a mass of 27.0 g1 mole of Al is formed upon the circulation of 3 moles of electrons1 mole of electrons has a charge of 96486 C (Faraday's constant)[tex]18.0gAl \times \frac{1molAl}{27.0gAl} \times \frac{3mole^{-} }{1molAl} \times \frac{96486C}{1mole^{-} } = 1.93 \times 10^{5} C[/tex]
1.93 × 10⁵ C circulate in 1.50 hours. The intensity is:
[tex]I = \frac{1.93 \times 10^{5} C}{1.50h} \times \frac{1h}{3600s} = 35.7 A[/tex]
Alkenes are more stable than alkanes. True or False
Answer:
Yes
Explanation:
Alkenes are relatively stable compounds, but are more reactive than alkanes because of the reactivity of the carbon–carbon π-bond. Most reactions of alkenes involve additions to this π bond, forming new single bonds.
Please help with this , it’s very important
Explanation:
a) Cr is acid K is base
b) Ca is base and the other left part is acid
c)Ca is base and F2 is acid
d) NH4 is acid and SO4 is base
A pencil has about 2.4 grams of graphite(carbon) in it. How many atoms is this?
Answer:
2
Explanation:
Determine the molar masses for each of the following elements, compounds, or molecules. Remember to round to the proper amount of Sig Figs!
Cu(OH)2 _ g/mol
Na2WO4 _ g/mol
Pd _ g/mol
KMnO4 _ g/mol
NH3 _ g/mol
Answer:
Explanation:
Cu(OH)2 _97.65 g/mol
Na2WO4 _293.82 g/mol
Pd _106.42 g/mol
KMnO4 _158.03 g/mol
NH3 _17.03 g/mol
Answer:
Explanation:
round 2 4-figs:
Cu(OH)2 97.65 g/mol
Na2WO4 293.8 g/mol
Pd 106.4 g/mol
KMnO4 158.0 g/mol
NH3 17.03 g/mol
How do you think the human population has changed over time? What makes you say that?
Answer:The world population increased from 1 billion in 1800 to 7.7 billion today. The world population growth rate declined from 2.2% per year 50 years ago to 1.05% per year. Other relevant research: World population growth – This article is focusing on the history of population growth up to the present.
Explanation: