Answer:
If there were multiple products, we can take each product and mixed with a sample of a pure compound that we suspect might be the same as the product. Then, we taking the melting point of this mixture that contains one of our product and pure sample. Then, we can observe the change in melting point, if there is no change in melting point or the melting stays in the same range of the pure compound. Then, the that product along with the pure sample are actually the same compound, not a mixture of two compounds. However, if the melting point for our pure sample compound changed or didn't stay in the same range after the mixing with on of our products. then we can conclude that this product and the pure sample are completely different compound, and indeed they are a mixture.
When a leaf of fresh sage or mint is rubbed ,the fragrance is
immediately obvious. Write a theoretical explanation for this observation
Answer: Volatile compounds present in the fresh sage leaf or mint leaf evaporate on rubbing.
Explanation:
When fresh sage or mint is rubbed on the skin or any other surface the volatile chemicals associated with the integral structure of the plant part get evaporated in the surrounding air and the vapors can be detected by the olfactory receptors present in the nose. These receptors take the smell or fragrance stimulus and generate impulses or signals which goes to brain and brain interprets the smell or fragrance.
Hydrogen bromide is found in volcanic gas. What is the chemical formula for
this compound?
Answer:
Hydrogen bromide, anhydrous appears as a colorless gas with a pungent irritating odor. Corrosive. Heavier than air. Prolonged exposure to fire or intense heat may result in the violent rupture and rocketing of the container. Long-term exposure to low concentrations or short-term exposure to high concentrations can result in adverse health effects from inhalation. Used to make other chemicals and as a catalyst in the manufacture of chemicals. Rate of onset: Immediate Persistence: Minutes to hours Odor threshold: 2 ppm Source/use/other hazard: Chemical manufacturing industry; very corrosive.
Explanation:
HBr
A 45g Aluminum spoon (specific heat 0.88J/g degree Celcius) at 24 degrees Celcius placed in 180ml(180g) of coffee at 85 degrees Celcius and the temperature of the two become equal. What is the final temperature?
Answer:
82 °C
Explanation:
Let the specific heat capacity of the coffee be that of water which is 4.2 J/g °C.
Now, at the final temperature, heat gained by Aluminum spoon ,Q equals heat lost by coffee, Q'.
Q = -Q'
Q = m₁c₁(T₂ - T₁) where m₁ = mass of aluminum spoon = 45 g, c₁ = specific heat of aluminum = 0.88 J/g °C, T₁ = initial temperature of aluminum spoon = 24 °C and T₂ = final temperature of aluminum spoon.
Q' = m₂c₂(T₂ - T₃) where m₂ = mass of coffee = 180 g, c₂ = specific heat of coffee = 4.2 J/g °C, T₃ = initial temperature of coffee = 85 °C and T₂ = final temperature of coffee.
So, Q = -Q'
m₁c₁(T₂ - T₁) = -m₂c₂(T₂ - T₃)
Making T₂ subject of the formula, we have
m₁c₁T₂ - m₁c₁T₁ = -m₂c₂T₂ + m₂c₂T₃
m₁c₁T₂ + m₂c₂T₂ = m₂c₂T₃ + m₁c₁T₁
(m₁c₁ + m₂c₂)T₂ = m₂c₂T₃ + m₁c₁T₁
T₂ = (m₂c₂T₃ + m₁c₁T₁)/(m₁c₁ + m₂c₂)
substituting the values of the variables into the equation, we have
T₂ = (180 g × 4.2 J/g °C × 85 °C + 45 g × 0.88 J/g °C × 24 °C )/(45 g × 0.88 J/g °C + 180 g × 4.2 J/g °C)
T₂ = (64260 J + 950.4 J)/(39.6 J/°C + 756 J/°C)
T₂ = 65210.4 J/795.6 J/°C
T₂ = 81.96 °C
T₂ ≅ 82 °C
Which of the following is the best definition of ethics?
A. The maintenance of a stable internal environment
B. Response to external stimuli
C. A set of guidelines for fair conduct during an experiment
D. A multistep process whose last step controls what happens in an
earlier step
Answer:
C
Explanation:
I believe the answer is C.
What are three ways that plastic pollution is harmful on land
Answer:
Plastic pollution are harmful on land because;
It can make human felt sick which is not healthy for us.Can someone do these? Brainliest included
Answer:
Explanation:
6. p⁺ e⁻
Ca²⁺ 20 18
F⁻ 9 10
O²⁻ 8 10
Na⁺ 11 10
7. Physical properties of matter are properties that can be measured or observed without matter changing to an entirely different substance. These include odor, boiling point, melting point, density, electrical conductivity and heat conductivity.
Separation of mixture:
Chromatography involves solvent separation on a solid medium.
Distillation takes advantage of differences in boiling points.
Evaporation removes a liquid from a solution to leave a solid material.
Filtration separates solids of different sizes.
Funnel partitioning with solvents. Solvent dissolves one component but not the other.
8.Bulk Elements => Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur & Phosphouous
Microminerals are those minerals needed in less than 100 mg quantities. Trace minerals or trace elements are usually needed in microgram quantities. Microminerals include iron, zinc, copper, iodine, fluoride, chromium, cobalt, selenium, manganese, and molybdenum.
Diatomic Molecules => H₂, N₂, O₂, F₂, Cl₂, Br₂, I₂
9. Electron Configurations
Na: 1s²2s²2p⁶3s¹ => valence = 3s¹
N: 1s²2s²2p³ => valence = 2s²2p³
Al: 1s²2s²2p⁶3s²3p¹ => valence = 3s²3p¹
Valence is the highest principle quantum number (or, principle energy level ~ ring) in the electron configurations.
10.moles of glucose = 450g/180.16 g/mol =2.50 moles
C₂H₆O₂ = 2(12) + 6(1) + 2(16) = 24 + 6 + 32 = 62 g/mole
which of the following is not good conductor of heat?
1-brass
2-stainless steel
3-bakelite
4-silver
Answer:
b. stainless steel
Explanation:
b) stainless steel is not good condoctor of heat
Consider the terms elements, compounds, and mixtures. What do you think each of
these is?
Answer:
Explanation:
Element -
It is the basic unit of matter, which cannot be broken down into substances by any way but can be combined to form new substances.
It is a pure substance.
It classifies into metals, non-metals, metalloids and noble gases.
Example - Hydrogen, Carbon, Oxygen
Compounds -
It is a combination of two or more elements.
It is a pure substance.
Through chemical reactions, they can be broken down into metals.
Example - Water, Carbon dioxide
Mixtures -
It is a combination of two or more elements or compounds or both.
The substances combined in a mixture are in a particular ratio.
Example - Chalk powder, Washing Soda
10. What do you understand by a balanced chemical equation? Explain with the an example.
in the photoelectric effect, what happens when light hits the metal
Answer:
electrons are knocked off atoms, causing electricity to flow.
Explanation:
Which elements on the periodic table are the least reactive? (1 point)
o the group with helium at the top
the group with hydrogen at the top
the group with carbon at the top
the group with fluorine at the top
Answer:
the group with helium at the top
Explanation:
I just took it
can you solve this.
I need it.
:) :):)
Answer:
12
45
ahagosmssjajjapaps3
Which of the following represents an endothermic reaction?
Select one:
a. S(s) +O2(g) → SO2(g) ΔH = -297kJ
b. 2NO2(g) → N2(g) + 2O2(g) + 33.8kJ
c. N2(g) + 2O2(g) + 90.4kJ → 2NO2
d. N2H4(g) + O2(g) → N2(g) +2H20(g) + 627.6 kJ
B because decomposition reactions are often caused by the application of heat to break up the bonds within the molecules, which will form the molecules that made up the decomposed molecule.
PLZ HELP which ia an example of a scientist using a physical model to describe a river
A. the scientists thinks of a river like a flow of electrons
B. the scientists builds a model of the river using plastic and a hose
C. the scientists writes an equation that describes the flooding of the river
D. the scientists uses a computer to predict how much water will flow
solubility of sodium chloride in water at 27 degree celsius is 22.7 in hundred ml of water the density of water is 1.0 gram per ml calculate the concentration of sodium chloride in term of mass percentage when dissolved in 500 ml of water
please tell me correct answer with solution
Answer:
of what grade it is of??
Explanation:
tell me then ill answer
what the recipe of momo
Answer:
Down is the recipe for momo..
Explanation:
recipe..
. Sieve the wheat flour carefully to remove lumps.
. Add water and knead the flour well to prepare a dough
. Remove the skin of the boiled potato ,cut into small pieces
. Heat the cooking oil in frying pan, and fry the pieces of onions cabbage green chili tomato pea etc.
. Prepare a mix veg stuffing by mixing potato other vegetables , green coriander and salt.
. Prepare a small balls of dough and roll it out of belna.
. Put 10 gm of mix vegetables stuff in the center of rolled dough and close it from all the sides to make a small ball.
. steam the momo for 10-15 minutes. After that it will be ready to serve.
. A sauce or pickle is usually eaten with momo.
Answer:
Explanation:
Sieve the wheat flour carefully to remove lumps.
11. A mixture of magnesium powder and lead (II) Oxide will react vigorously when heated but no reaction occurs when a mixture of magnesium oxide and lead powder are heated, a) Explain the observation. b Which of the two substances, magnesium or lead(IT) Oxide is; i) Oxidized in the reaction? ii) Oxidizing agent? C Which is the most reactive metal Please helpA
Answer:
17
Explanation:
i need points
I NEED HELP ASAP!!!
All of the following are examples of ways to increase mechanical advantage EXCEPT:
Select one:
a.adding more threads to a screw
b.making a wheel larger than an axle
c.increasing the length of a ramp
d.increase the steepness of a ramp
im doing a escape room and i dont know what the answer is
Answer:
thats pink floyds album cover LOL
but the answer is to prism
hope this helps :)
What happens when acetylene reacts with silver powder?
Which missing item would complete this alpha decay reaction?
21CF-247 Cm +
Answer:
the atomic number decreased in 2, from 100 to 100 - 2 = 98. 3) Hence the formed atom has atomic number 98, which is californium, Cf, and the isotope is californium - 253. 4) The item that completes the given alpha decay reaction is: ₉₈²⁵³ Cf.
Explanation:
summer school is over, and I'm feeling self-destructive. Take all of my points and have a good night. 3/3
ayo thanks mate :0000000000000000000000
Suggest a way that a scientist could create an even more accurate model of universe expansion
Answer:
Between galaxies, retake the measurement.
Explanation:
Among both galaxies, reiterate the measurements. Instead of utilising a balloon, a scientist might create a model that shows in which everything really is and how cosmos is expanding rather than expanding. By inflating up the atmosphere to 1/2, 3/4, and full size, continue the operation.
What would you need to do to calculate the molality of 10 g of NaCl in 2 kg of
water?
A. Convert the 2 kg of water to liters of water.
O B. Convert the 10 g of NaCl to moles of NaCl.
C. Convert the 2 kg of water to moles of water.
O D. Convert the 10 g of NaCl to kg of NaCl.
Answer:
O B. Convert the 10 g of NaCl to moles of NaCl.
Explanation:
The formula for finding the molality is m=moles of solute/kg of solvent. The solute for this question is NaCl and the solvent is water.
(10g NaCl)(1 mol NaCl/58.44g NaCl)=0.1711 mol NaCl
58.44 is the molar mass of NaCl
m=0.1711 mol NaCl/2 kg H2O
m=0.085557837
True or false, The universal gas constant, R, is . 0821 when we use mm Hg as our unit for pressure
Answer:
This is true.
Explanation:
R should be 0.0821
Good luck!
How did elements get to earth?
the universe formed through the big bang explosion, all of the elements on Earth have been cooked for billions of years in stars and then released in the universe through super- nova explosions.
ASAP
Which of the following gases will have the highest rate of effusion at a given temperature?
Cl2
He
O2
Ne
Answer:
chlorine Will be at highest
Explain the bonding that occurs between sodium and chlorine. Specifically, what kind of bonding takes
place, what’s the name of the resulting compound, and what properties would you expect this compound to
have with respect to water?
Answer:
About bonding
Explanation:
A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bond.
Answer:
An ionic bond occurs between sodium and chlorine where sodium has one electron while chlorine has seven electrons. The electron from sodium is lost and transferred to a chlorine atom which results in a sodium ion with a charge of one+ and a chloride ion with a charge of one-. These oppositely charged ions attract each other making a balanced charge to make a compound that is electrically neutral.. Sodium cation (Na+) and chlorine anion (Cl-) are attracted to each another to form sodium chloride (table salt). When dissolved in water, the sodium and chloride ions are strongly attracted to the polar water molecules because of ion-dipole interactions.
Explanation:
Small quantities of spilled acids can be made safe with *
1 point
o gasoline.
alcohol.
water.
sodium bicarbonate solution.
Answer:
sodium bicarbonate solution
ASAP worth 15 points also
