Answer:
what is meaning of this.
Answer:
On April 30, 1789, George Washington, standing on the balcony of Federal Hall on Wall Street in New York, took his oath of office as the first President of the United States.
Helpppppppkklepepepepepepepe
Which of the following does NOT involve a physical change?
Answer:
Degradation of matter
Explanation:
Physical change is a temporary change.
What is the empirical formula of CoH1803? (4 points)
-O CH30
-C₂H50
-C₂H₂O
-O C₂H5O5
Answer:
-O CH30
Explanation:
My Head Is About To Explode
5. Which element would form
covalent bond with Oxygen (0)
Sodium (Na)
Calcium (Ca)
Aluminum (AI)
Selenium (Se)
List the metals that form only one type of ion (that is, metals whose charge is invariant from one compound to another). What are the group numbers of these metals
this question is in reference to the formation and naming of ionic compounds. Specifically, they want you to give examples of three ionic compounds with a metal to nonmetal ratio of 2 to 1. That means we need to have two metal atoms to metal ions, which are typically cat ions for every one non metal atom or an ion. In order for this to occur, we need to have the metal with half the charge of the nonmetal or the non metal with double the charge of the metal. So an example might be something like sodium sulfide. Sodium has one valence electron. It can give up sulfur needs to valence electrons in order to achieve an octet. So we need to. Sodium seems to give up one electron each to total so that sulfide can achieve an octet. Another one might be potassium oxide. Similar scenario. We've got potassium giving up one valence electron oxygen requiring too. So we need to potassium to supply the to valence electrons that oxygen needs to achieve an octet and lithium. Also in Group one A and alkali metal wants to give up just one valence electron to achieve an octet well to achieve, I guess a duet to be more like helium, and so it gives up one. If we have two of them, then we can provide the to valence electrons that sulfur needs. So this is sodium sulfide, potassium oxide and lithium sulfide. Remember when we name Ionic compounds? We named the Cat Ion with the name of the element and the anti on with the name of the Element, but with the ending oven of ID, a suffix of ID because each one of the cat ions donated their valence electrons to the anti on so the an ion could achieve an octet. Then all of the's will have an octet of valence electrons. Sulfur had six sodium had one. There were two of them, so we have a total of eight.
The metals that can form only one type of ion are Li, Al, Ca, Ba, Rb, W,Na, Mg and Sr. They are called alkali metals.
Cobalt, Co is stable in both +2 and +3 oxidation state. So it can variable.
Lithium, Li only have +1 charge. So it is invariable from one compound to other.
Lead, Pb is variable as it has +2, +4 charge in which it is stable.
Pd has +2, +4 charge in which it is stable. So, It is variable.
Copper, Cu has +1, +2 charge. It is also variable. Potassium, K has only +1 charge. It is invariable. Aluminum, Al has only +3 charge. It is invariable.
Cesium, Cs is only stable in +1 charge. It is invariable. Molybdenum, Mo is stable in +4 and +6. It is variable. Calcium, Ca and Barium Ba are stable in +2 charge. It is invariable.
Rubidium, Rb is stable in +1 charge. It is invariable. Tungsten, W is stable in +6 charge. It is invariable. Iron, Fe is stable in +2, +3 charge. It is variable. Sodium, Na is stable in +1 charge. It is invariable. Mg and Sr are stable in +2 charge. It is invariable. Vanadium, V has +2, +3, +4, +5 charges. So, It is variable.
To know more about alkali metals
https://brainly.com/question/18153051
#SPJ3
How are metals, metalloids, nonmetals grouped
no I will not please put you because that's the god of the Bible
Metals are good conductors of heat and electricity, and are malleable (they can be hammered into sheets) and ductile (they can be drawn into wire).
Nonmetals are (usually) poor conductors of heat and electricity, and are not malleable or ductile; many of the elemental nonmetals are gases at room temperature, while others are liquids and others are solids.
The metalloids are intermediate in their properties. In their physical properties, they are more like the nonmetals, but under certain circumstances, several of them can be made to conduct electricity.
hope this answer helped u, if u can pls mark me as the brainliest. :)
need help with this pleaseeeee
Answer:
1) 1, 1
3)1, 1
4) 1, 2
5) 2, 1
6) 1, 5
7) 2, 5
Which best describes the energy change that takes place during deposition?
Heat energy released by the substance
Heat energy is maintained by the substance
Heat energy is slowly gained by the substance
Heat energy is quickly absorbed by the substance
Answer:
heat energy released by the substance
The energy change that takes place during deposition is that heat energy is released by the substance. This statement is true about deposition.
Deposition is a phase transition that occurs when a gas is converted directly to a solid without passing through the liquid state. During deposition, energy is released by the gas particles and absorbed by the surface, resulting in a decrease in the energy of the gas particles and an increase in the energy of the surface particles.As a result, the substance releases heat energy as it changes from a gas state to a solid state.
Therefore, the correct option is:Heat energy released by the substance.
Learn more about heat energy,here:
https://brainly.com/question/29210982
#SPJ5
Stems are important plant structures because they _________.
A.
are the main sites of photosynthesis for plants
B.
are the only site of water and nutrient transport
C.
allow plants to absorb water and nutrients from the soil
D.
give the plant structure and support
Answer:
D
Explanation:
Answer:
for plato users, the answer is: give the plant structure and support
Find the volume of 0.160 M sulfuric acid necessary to react completely with 75.0 g sodium hydroxide.
The volume of 0.160 M sulfuric acid necessary to react completely with 75.0 g sodium hydroxide is 0.15L
The reaction of sulphuric acid and sodium hydroxide is expressed as:
[tex]2NaOH + H_2SO_4 ==> Na_2SO_4 + 2H_2O[/tex]
Determine the moles of NaOH present
Molar mass of NaOH = 23 + 16 + 1 = 40g/mole
Given that mass of NaOH is 75.0g
Mole of NaOH = 75/40 = 1.875moles
Determine the number of moles [tex]H_2SO_4[/tex] needed to react with 1.875 moles NaOH
Moles of [tex]H_2SO_4[/tex] = [tex]\frac{1.875}{2} = 0.9375moles of H_2SO_4[/tex]
Recall that volume = Molar mass * number of moles
Volume of [tex]H_2SO_4[/tex] = 0.160 * 0.9375
Volume of [tex]H_2SO_4[/tex] = 0.15L
Hence the volume of 0.160 M sulfuric acid necessary to react completely with 75.0 g sodium hydroxide is 0.15L
Learn more here: https://brainly.com/question/837939
A gas has a volume of 1140 ml at 37 ºC and 620 mm Hg pressure. Calculate its volume at STP.
1.900
2.800
3.819
4.1000
Answer:
3. 0.819L (819 mL)
Explanation: Before we go about solving this, we need to do some conversions prior to using the gas law, the gas law is as follows...
P(atm)*V(L)=n(mol)*r(constant)*T(in kelvin)
So here are all the conversions you need.
620 mm Hg -> 0.816 atm
1140 mL -> 1.14 L
37 C -> 310.15 K
After plugging in our new converted values, we will proceed to solve the number of moles of the gas present, our n value, so our equation will look like this...(Note: Constant r in this case is 0.08206 L*atm/K*mol)
(0.816 atm)(1.14 L) = n(0.08206)(310.15)
Solving for n we get 0.03653 moles.
Now our second part is to figure out the volume AT STP (standard temperature/pressure). In the STP conditions, your temperature defaults to 0 C (273.15 K) and 1 atm. Now there is an easier way to do this, but I'll also show the more comprehensive way. Here is the easier method...
Since 1 mole of every gas occupies 22.4 L at STP, we can simply multiply this by our number of moles. So (22.4L)(0.3653 mol) to give us 0.818272.
However, a more accurate answer can be given like this...
Plugging n back into the same equation and this time resetting pressure to 1 atm and temperature to 273.15 K and conserving our number of moles we get...
(1 atm)(v) = (0.03653 mol)(0.08206)(273.15 K)
v = (0.03653)(0.08206)(273.15)
v = 0.8188 L = 0.819 L or 819 mL
Hydrocarbons (alkanes, alkenes, alkynes) have all the properties below except one.
Which is not a property of hydrocarbons?
A.nonpolar
B.high melting and boiling points
C.insoluble in water
D.flammable
Answer:
B
Explanation:
The answer is B. All hydrocarbons are nonpolar, they are insoluble in water and they are highly flammable. Now, not all hydrocarbons have high boiling and melting point. For example, methane (CH4) has a boiling point of something clode to -161°C, and that is low. The boiling point increases when the number of carbon atoms in a compound increases, and based on methane and this theory, not all hydrocarbond have a high boiling point. This makes option B be the correct answer.
can someone tell me how to find moles in acid&base equations (simple explination pls)
Answer:
When the base neutralizes the acid, the number of moles of H+ = the number of moles of OH-. Therefore, the number of moles of H+ = 0.0125 moles. Every mole of HCl will produce one mole of H+; therefore, the number of moles of HCl = number of moles of H+. The concentration of the HCl is 0.25 M
help! giving brainliest.
Answer:
A
Explanation:
will group 2 elements gain electrons to bond with non-metals in group 16 in a 2:1 ratio
methane the principal component of natural gas is used for heating the cooking the combustion process is
Answer:
CH4 + O2 = CO2 + 2H2O
Explanation:
carbon dioxide and water is given off
Ana was setting up a circuit to make a buzzer buzz. She didn’t have any wires, so she needed to find
something that had the same properties as wires. Which of the following would work for Ana’s circuit?
A. A steel knife
B. A wood chopstick
C. A plastic straw
D. A glass tube
Answer:
should be a or d, though im leaning towards d more. sadly can't narrow it down 100%. b nor c are correct since they are made out of wood and plastic which cannot allow electricity to pass by. copper and metal are effective conductors of electricity, which a steel knife and a glass tube is made out of.
draw clear, colorful and understandable diagrams of the metabolism of carbohydrates and lipids?
(you can have 2 separate ones, or you can combine them into one)
Answer:
Refer to the attachments!!
Explanation:
4. A student performs four trials of an investigation to determine the boiling point of water. How should the student handle the results?
A. The student should take the average of the minimum and maximum value of the results.
B. The student should use the value that is closest to 100ºC.
C. The student should use the maximum value of the results.
D. The student should take the average of the results from all four trials.
Answer:
i think its D
Explanation:
In order to get maximum accuracy, student should take average of results from all four trials.
What is accuracy?Accuracy in terms of chemistry can be defined as to how close a measurement is to the true value.There are three types of accuracy:
1) Point accuracy-It means accuracy is present at that point of scale only.It does not give any information about the accuracy of the instrument.
2)Percentage of true value--It is the accuracy which is determined by identifying accuracy of the instrument and comparing it with the measured true value.
3)Percentage of scale range- It is the accuracy which determines accuracy of the measurement.
Accuracy in case of instruments is neglected up to ±0.5 percent.Accuracy of measurements can be increased by taking multiple measurements and taking into account human errors.
Learn more about accuracy,here:
https://brainly.com/question/15276983
#SPJ2
What’s the answer to this
Answer: 5
Explanation:
please brainliest me
I believe it is 3
Answer:
Explanation:
A student wants to show the transfer of heat energy without matter which investigation design would best help the student
A) an investigation of radiation through a current in a fluid
B) an investigation of radiation through electromagnetic waves
C) an investigation of conduction through collisions between particles in space
D) an investigation of conduction through the movement of particles through a solid
Answer:
C
Explanation:
According to the concept of thermal energy, transfer of heat energy can be depicted by investigation of conduction through collisions between particles in space.
What is thermal energy?Thermal energy is defined as a type of energy which is contained within a system which is responsible for temperature rise.Heat is a type of thermal energy.It is concerned with the first law of thermodynamics.
Thermal energy arises from friction and drag.It includes the internal energy or enthalpy of a body of matter and radiation.It is related to internal energy and heat .It arises when a substance whose molecules or atoms are vibrating faster.
These vibrating molecules and atoms collide and as a result of which heat is generated in a substance , more the collision of particles , higher is the thermal energy.
Learn more about thermal energy,here:
https://brainly.com/question/3022807
#SPJ5
Airflow through a long 0.2m square air conditioning duct maintained the outer duct surface temperature at 10degree.if the horizontal duct is uninsulated and exposed to air at 35degree in the crawl space beneath at home.
What is the heat gain per unit length of the duct.
Answer:
125°C/m
Explanation:
The difference in temperature will be:
35 - 10 = 25
The outer duct surface is heated 25°C by the air from 10°C to 35°C;
This heat gain is simply divided by 0.2m to get heat gain per unit length:
25/0.2 = 125
125°C/m
If you're American, this will be °F I believe, so the answer will be:
125°F/m
the farm is a place where lot's of different__________and________live.goats have________that arch backward.the horns keep them___________.
horns insects animals protected
dog's are man's best friend.dogs eat ______to keep them energetic.dogs permanent__________are ________.a dogs teeth serve as _______and as tools for ________or________food
meat cutting powerful teeth weapon tearing
Answer:
plantsanimalshornsto protect it selfkaleliving with peoplescaring itspecialbite eatExplanation:
I know it's right, because this answer is from my self and I hope it's help to us. keep learning and God bless.
Write a balanced chemical equation for the complete combustion of methanol, ethanol, propanol, butanol and paraffin wax(C25H52). This information will be needed for the experiment. Transfer the answer to the data sheets also. (10 pts)
Answer:
Explanation:
1. Methanol:
CH3OH + O2 ---> CO2 + 2H2O
2. Ethanol:
C2H5OH + 3O2 ----> 2CO2 + 3H2O
3. Propanol:
2C3H7OH + 9O2 ------> 6CO2 + 8H2O
4. Butanol
C4H9OH + 6O2 -------> 4CO2 + 5H2O
5. Paraffin Wax:
C25H52 + 38O2 ----> 25CO2 + 26H2O
A sample of carbon dioxide gas has a pressure of 8.33 bar and a volume of 10.3 mL at a temperature of 29.1 °C. How many
molecules of carbon dioxide gas are in the sample?
molecules:
A moon orbits in a roughly circular path around a planet with a mass of 8.6 x 1023 kg. The distance from the center of the moon to the center of the planet is 7.04 x 106 meters. Calculate the speed of the moon in m/s.
Explanation:
A moon orbits in a roughly circular path around a planet with a mass of 8.6 x 1023 kg. The distance from the center of the moon to the center of the planet is 7.04 x 106 meters. Calculate the speed of the moon in m/s.
a
A molecule that experiences London dispersion forces is
likely to have a • boiling point than a molecule
experiencing a dipole-dipole interaction.
pls
Answer:
it should be the second one since London dispersion causes interaction between molecules.
hope I helped.
Generally non ionic species with no polarity forms the London -dispersion bonds. London dispersion is weaker than the dipole-dipole interaction and hence it have less boiling point.
What is boiling point?Boiling point of a substance is the temperature at which the substance changes from liquid state to gaseous state or vapor where, the two states are in equilibrium.
Boiling of a substance depends on the molecular weight, bond type,temperature, pressure as well as purity of the substance.
London dispersion force is formed between two non-polar atoms. These atoms when come closer they attains a temporary polar nature and gets bonded.
Dipole-dipole bond is formed between two atoms of permanent dipole moment and they are polar compounds. Thus dipole-dipole interaction is stronger than London dispersion interaction. A strong bond needs more energy to boil.
Hence, molecules with Dipole-Dipole bond is having higher boiling point.
To find more about boiling point, refer the link below:
https://brainly.com/question/2153588
#SPJ2
Finding dead insects or mouse droppings in the kitchen indicates which of the following: Pest infestation Chemical contamination Food spoilage Cross contamination
Finding dead insects or mouse droppings in the kitchen is an indication of pest infestation.
Pests are living organisms that are capable of spreading diseases, causing economic damages, or generally constituting nuisance to the environment.
Pest infestation occurs when there is a high number of pests in the environment. When this occurs, their activities are felt in the environment in terms of causing a nuisance, and damaging properties or contaminating foods.
More on pest infestation can be found here: https://brainly.com/question/13483095
How many atoms...
NAC2H3O2
Answer:
one Sodium (Na) atom, two oxygen (O) atoms, two carbon (C) atoms, and three hydrogens (H) atoms
Explanation:
13500 mL convert to milliliters of mercury
Answer:approximately 5.627 × 1019 milliliters
Explanation:
NEED ANSWER ASAP!!
A mining company is looking for ways to save money on the process they use to discover new mineral resources while also reducing the impact that the mining process has on the environment.
Which improved technology would
best achieve this goal?
O fracking
O drilling technology
O extraction technology
O geological Surveying
Answer:
extraction technology.....