a cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch or as a dark silhouette against other luminous matter.
a clouded spot on the cornea causing defective vision.
Hope this helped
Answer:
A cloud of gas and dust in outer space, visible in the night sky either as an indistinct bright patch or as a dark silhouette against other luminous matter.
Explanation:
I need helpp!!!!!!!!!
19) What did Rutherford's experiment show?
Answer:
experiment showed that the atom is mostly empty space with a tiny, dense, positively-charged nucleus.
Explanation:srry im late but i dont be on it like that hoped it helped tho srry
1) Chemistry is a (physical/biological) science?
Answer:
Explanation:
Biological.
I hope I helped you! :)
what element has 3 protons 2 neutrons and 2 electrons
Answer:
helium i think
Explanation:
What happens to the principle energy level number when moving from s to p sub levels
Answer:
The principal energy level remains the same
Explanation:
A principal energy level is one defines where electrons reside in an atom and that can contain one or more sub levels and have 2·n² number of electrons located in different sub levels within the energy level. Therefore, when moving up from s to p within the same principal energy level, the principal energy level does not change value.
brainly or jiskha
choose wisely
Answer:brainly
Explanation:
absolutely brainly
full of help and knowledge
Define self reduction reaction.
Answer:
Self-reduction is a reaction in which no external reducing agent is required. It is called self-reducing because copper oxide itself reduced the copper sulfide to give copper and sulfur dioxide.
Atoms of the same element can have different forms; for example, carbon-12 and carbon-14.
What causes the different forms?
What are these forms called?
Who were the terrorists that attacked the united states on September 11, 2001
What are the boiling points and freezing points (in oC)of a solution of 50.3 g of I2in 350 g of chloroform? The kb= 3.63 oC/m, the kf= 4.70 oC/m for CHCl3, and the molar mass of I2is 253.8 g/mol. The normal boiling point for CHCl3is 61.2 oC, and the normal freezing point for CHCl3is -63.5 oC.
Answer:
F.p ≈ - 66.16⁰c
B.p ≈ 59.1⁰c
Explanation:
Normal boiling point = 61.2⁰c
Normal freezing point = -63.5⁰c
Kb = 3.63⁰⁰ c/m
Kf = 4.70⁰ c/m
molar mass = 253.8 g/mol
solvent = 350 g = 0.35 kg
calculate The new freezing point and Boiling point
First we have to find the molality = number of moles / solvent in kg
= 0.198 / 0.35 = 0.5657 M
Hence the new freezing point can be calculated as
Normal freezing temp - new freezing temp = Kf * molality
= -63.5 - F.p = 4.7 * 0.5657
F.p = -63.5 - 2.6588 ≈ - 66.16⁰c
Boiling point
Normal boiling point - new boiling point = Kb * molality
= 61.2 - B.p = 3.63 * 0.5657
B.p = 61.2 - 2.0535 ≈ 59.1⁰c
When potassium chlorate decomposes to potassium chloride and oxygen gas is it a physical or chemical change?
How does the arrangement of atoms differ in crystals and glass?
How does the arrangement of atoms differ in a crystalline and a noncrystalline substance? Crystals have well organized arrangement of atoms. Non crystals have irregular unorganized arrangement of atoms. You just studied 13 terms!
The graph below shows the speed of a downhill
skier during a period of several seconds. Use the
graph to answer Question 13.
16
12
Speed (m/s)
8
0
1
3
3
2
Time (s)
13. Read Graphs What is the skier's acceleration?
Answer:
16
Explanation:
what is the density or 40 mL of liquid that has a mass of 20 grams help ASAP
Answer:
Density of 40 mL of liquid that has a mass of 20 g = 20 / 40 = 0.5 g / cc
Answer:
Density= mass/volume
Density= 20/40
Density= 0.5g/mL
Naturally occurring boron has an atomic mass of 10.810 amu consists of two isotopes. One of those isotopes is 10B with an isotopic mass of 10.0129 amu and an abundance of 19.9%. What is the isotopic mass of the other isotope?
Answer:
boron has an atomic mass of 10.810 amu consists of two isotopes.
Answer:
boron has an atomic mass of 10.810 amu consists of two isotopes.
Explanation:
Which solution has the lower freezing point in each of the following pairs? (a) 11.0 g of CH3OH in 100. g of H2O or 22.0 g of CH3CH2OH in 200. g of H2O? CH3OH/H2O CH3CH2OH/H2O Both solutions have the same freezing point. (b) 20.0 g of H2O in 1.00 kg of CH3OH or 20.0 g of CH3CH2OH in 1.00 kg of CH3OH? H2O/CH3OH CH3CH2OH/CH3OH Both solutions have the same freezing point.
Answer:
See explanation
Explanation:
(a)
From the data provided;
Mass of methanol =11.0 g
Mass of solvent (H2O) =100 g = 0.1 kg
Molar mass of CH3OH =32.04 g/mol
Number of moles of solute = 0.343 mol
molality(m) of methanol = 3.43 m
Also,
Mass of ethanol =22.0 g
Mass of solvent (H2O) =200 g = 0.2 kg
Molar mass of C2H5OH =46.068 g/mol
Number of moles of solute = 0.477 mol
molality(m) of ethanol= 2.38 m
The greater the concentration of a solution, the higher the freezing point of solvent will be depressed. Therefore, higher molality, leader to a greater decrease of the freezing point.
Therefore, the freezing point of methanol CH3OH/H2O is lower than the freezing point of ethanol.
b)
Mass of solvent = 1 kg
Mass of water = 20g or 0.02 Kg
Molar mass of water = 18 gmol-1
Number of moles of solute = 20g/18 gmol-1 = 1.11 moles
Molality= 1.11 moles/1 kg = 1.11 m
Also;
Mass of ethanol = 20 g = 0.02 kg
Mass of solvent = 1.00 Kg
Molar mass of solute = 46 gmol-1
Number of moles of solute = 20g/ 46 gmol-1 = 0.43 moles
Molality= 0.43 moles/ 1 kg = 0.43 m
The greater the concentration of a solution, the higher the freezing point of solvent will be depressed. Therefore, higher molality, leader to a greater decrease of the freezing point.
Therefore, the freezing point of water H2O/CH3OH is lower than the freezing point of ethanol.
Which of the following gases is the least soluble in water and why? CO2, SO3, N2, NH3, HCl.
Answer:
SO3
It has the highest molar mass value and thus would be the least soluble
Explanation:
In this question, we want to know which of the gases is the least soluble in water.
The easiest way to do this is to calculate the molar masses of these gases. The gas with the highest molar mass is the heaviest and thus will be the least soluble in water
For CO2 - molar mass is 44 g/mol
For SO3- molar mass is 80 g/mol
For N2- molar mass is 28g/mol
For NH3-molar mass is 17g/mol
For HCl- molar mass is 36.5 g/mol
From the molar masses, we can see that the molar mass of the ammonia gas is the lightest and thus, it is the most soluble.
The mass of the sulphur vi oxide is the highest and thus it is the heaviest and the least soluble in water
What characteristics identify a substance?
Answer:
All substances can be characterized by their unique sets of physical and chemical properties.
An outside thermometer reads 57°F. What is this temperature in °C? Round your answer to the nearest whole number.
1. subtract 32 from 57 (57-32)
2. multiply 5/9 by (57-32)
3. equation: (57-32)×5/9
Answer:
14°C
Explanation:
Temperature is the degree of hotness or coldness of an object. It is measured using an instrument called THERMOMETER. There are different units of measuring temperature which are interconvertible. The units are Fahrenheit (°F), Celsius (°C), Kelvin (K) etc.
Significant figure of 0.06300
Answer:
Number of Significant figures is : 4
Scientific Notation is: 6.3 x 10^-2
EXTRA HELP
Explain why CaCl2 is likely to have properties similar to those of CaBr2
Answer:
Because both CaCl2 and CaBr2 both contain elements (Chlorine and Bromine) from the same group (group 7)
Explanation:
Elements are placed into different groups in the periodic table. Elements in the same group are those that have the same number of valence electrons in their outermost shell and as a result will behave similar chemically i.e. will react with other elements in the same manner.
Chlorine and Bromine are two elements belonging to group 7 of the periodic table. They are called HALOGENS and they have seven valence electrons in their outermost shell. Hence, when they form a compound with Calcium, a group two element, these compounds (CaCl2 and CaBr2) will possess similar properties because they have elements that are from the same group (halogen group).
The compounds of [tex]\rm CaCl_2[/tex] and [tex]\rm CaBr_2[/tex] have similar chemical properties as they are constituted of elements belonging to the same group.
The compounds with the elements belonging to the same group have similar chemical properties. It has been given that the chemical properties of elements have been dependent on the number of valence electrons.
The given compounds have been calcium chloride and calcium bromide. The calcium has been the same cation in the compounds however, the anions are different.
The anion Cl and Br both belongs to group 17 and have 7 valence electrons. Thus, the compounds have been possessing similar chemical properties.
Thus, calcium chloride and calcium bromide are more likely to have similar chemical properties as they have elements belonging to the same group.
For more information about chemical properties, refer to the link:
https://brainly.com/question/18327661
Some studies have found that when a person mimics an angry expression, their temperature actually rises.
O A True
OB.
False

A scuba tank has pressure of 195 kpa at temperature 10 c the volume of the tank is 350 L how many grams of air ins in the tank?
Answer:
[tex]m=840.88g[/tex]
Explanation:
Hello,
In this case, considering the ideal gas equation as:
[tex]PV=nRT[/tex]
We can first compute the moles of air at the given conditions of 195 kPa (1.92 atm), 10 °C (283K) and 350 L:
[tex]n=\frac{PV}{RT}=\frac{1.92atm*350L}{0.082\frac{atm*L}{mol*K}*283K}\\ \\n=29.03molAir[/tex]
Next, since the molar mass of air is 28.97 g/mol, the mass is computed to be:
[tex]m=29.03mol*\frac{28.97g}{1mol} \\\\m=840.88g[/tex]
Best regards.
Consider the following balanced equation:3Ca(NO3)2(aq) + 2Na3PO4(aq) → Ca3(PO4)2(s) + 6NaNO3(aq)If 24.2 moles of Na3PO4(aq) reacts with an excess of Ca(NO3)2(aq) to produce 50.6 moles of NaNO3(aq), what is the percent yield of the reaction?
Answer:
69.7% is percent yield
Explanation:
Based on the reaction:
3Ca(NO3)2(aq) + 2Na3PO4(aq) → Ca3(PO4)2(s) + 6NaNO3(aq)
2 moles of Na3PO4 react producing 6 moles of NaNO3.
As 24.2 moles of Na3PO4 react, theoretical moles of NaNO3 produced are:
24.2 moles Na3PO4 * (6 moles NaNO3 / 2 moles Na3PO4) =
72.6 moles of NaNO3
As there are produced 50.6 moles of NaNO3, percent yield is:
50.6 moles NaNO3 / 72.6 moles NaNO3 =
69.7% is percent yieldGive the name of each ion.
S2-
N3-
Answer:
The answer is Sulphur and Nitrogen ion
Hover over answer image to enlarge
8)
Which part of the atom cannot have its location accurately determined and is modeled by a cloud around the center of
the atom?
-0)
A)
electron
B)
neutron
nucleus
D)
proton
An atomic nucleus is composed of
)
Which of the following fluids has the greatest concentration of potassium ions?
a. Extracellular fluid (ECF).
b. Interstitial fluid.
c. Cytosol.
d. Plasma.
Matter are anything that is made up of atoms. The quantity of matter can be observed only on the basis of mass and volume calculation. Therefore, the correct option is option C.
What is matter?
Matter is a substance that has some mass and can occupy some volume. The matter is mainly used in science. Matter can be solid, liquid or gas.
Matter is anything that is made up of atoms. Anything around us that can be physically seen and touched are matter. Ice, water and water vapors are example of matter.
Cytosol is the liquid medium contained within a cell. The cytosol is a component of the cytoplasm. Out of given option cytosol has the greatest concentration of potassium ions. The cytoplasm does not include the nucleus.
Therefore, the correct option is option C.
To learn more about matter, here:
https://brainly.com/question/4562319
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at what height is an object that has a mass of 16kg, if it’s gravitational potential energy is 7500J?
Answer:
46.875
Explanation:
P.E=MGH
7500=16*10*h
7500=160h
h=7500/160
h=46.875
Select the meaning of the word sign that best
describes this image.
O to write as a signature
P
a gesture used to express an idea
O an object that conveys meaning
O a symbol used to abbreviate words
WHAT IS ITRT
Answer:
an object that conveys meaning
Explanation:
Answer:
c
Explanation:
Helium is more reactive than magnesium.
TRUE
FALSE
Answer: FALSE
Explanation: Magnesium is more reactive.
Hope this helps!
Answer:
False
Explanation:
Magnesium is more reactive.