Answer:
one star
In our solar system, there is only one star that we know of – the sun! Our solar system is very unique in that is only has one star. Most other solar systems have at least two stars. These are called binary systems.
Explanation:
[tex]\huge\purple{Hi!}[/tex]
Some estimates peg the Milky Way's star mass as having 100 billion "solar masses," or 100 billion times the mass of the sun. Averaging out the types of stars within our galaxy, this would produce an answer of about 100 billion stars in the galaxy. This is subject to change, however, depending on how many stars are bigger and smaller than our own sun. Also, other estimates say the Milky Way could have 200 billion stars or more.
Which of the following is included in the study of Geology?
a : the composition of the sun
b : the composition of air
c : the composition of water
d : the composition of the materials that make up the planet
1 Na2CO3(aq) + 1 CaCl2(aq) → 1 CaCO3(s) + 2 NaCl(aq) 4. Use the balanced chemical equation from the last question to solve this situation: You combine 0.5 grams of Na2CO3 with excess CaCl2. How many grams of NaCl would you expect this reaction to produce? Show all work below.
0.6 g NaCl
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableStoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[RxN - Balanced] Na₂CO₃ (aq) + CaCl₂ (aq) → CaCO₃ (s) + 2NaCl (aq)
[Given] 0.5 g Na₂CO₃ reacted with excess CaCl₂
Step 2: Identify Conversions
[RxN] Na₂CO₃ → 2NaCl
Molar Mass of Na - 22.99 g/mol
Molar Mass of C - 12.01 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of Cl - 35.45 g/mol
Molar Mass of Na₂CO₃ - 2(22.99) + 12.01 + 3(16.00) = 105.99 g/mol
Molar Mass of NaCl - 22.99 + 35.45 = 58.44 g/mol
Step 3: Stoichiometry
Set up: [tex]\displaystyle 0.5 \ g \ Na_2CO_3(\frac{1 \ mol \ Na_2CO_3}{105.99 \ g \ Na_2CO_3})(\frac{2 \ mol \ NaCl}{1 \ mol \ Na_2CO_3})(\frac{58.44 \ g \ NaCl}{1 \ mol \ NaCl})[/tex]Multiply/Divide: [tex]\displaystyle 0.551373 \ g \ NaCl[/tex]Step 4: Check
Follow sig fig rules and round. We are given 1 sig fig.
0.551373 g NaCl ≈ 0.6 g NaCl
Which feature forms as a result of conduction between magma and water?
Answer:
h
Explanation:
get into
How many moles are in 0.532g Ca(OH)2?
Answer:
0.0072mole
Explanation:
Given parameters:
Mass of the compound given = 0.532g
Unknown:
Number of moles = ?
Solution:
To solve this problem, we need to use the expression below:
Number of moles = [tex]\frac{mass}{molar mass}[/tex]
Molar mass of Ca(OH)₂ = 40 + 2(16 + 1) = 74g/mol
Number of moles = [tex]\frac{0.532}{74}[/tex] = 0.0072mole
Need Help On this one two anybody !! pls
Answer:
26. Single Displacement
27. Synthesis
28. Decomposition
29. Combustion
30. Double Displacement
31. Combustion
32. Double Displacement
33. Decomposition
Explanation:
Hope it helped!
One way to determine if a rock sample is metamorphic is by:
a.
finding fossil evidence
c.
noting a crystalline structure in its particles
b.
noticing light and dark color bands
d.
all of the above
One way to determine if a rock sample is metamorphic is by "noticing light and dark color bands."
What is the system of communication that involves an alphabet in which letters are represented by combinations of long and short
signals of light or sound?
A
Email
B)
Morse code
Binary code
D
Digital Signal Reception
Wireless intern
Answer:
B)
Morse code
Explanation:
Morse code is a communication system developed by Samuel Morse, an American inventor, in the late 1830s. The code uses a combination of short and long pulses – dots and dashes, respectively – that correspond to letters of the alphabet.
Answer:
b
Explanation:
I got it right on the exam. Morse code is your answer.
how is copper sulphate different to copper sulphide in terms of the elments it contains
Answer:
An Element is a substance made up of only one type of atom as like gold, copper, oxygen, etc.
Copper sulphate with molecular formula [tex](CuSO_4)[/tex], the elements are copper, sulphur and oxygen. It is formed by combination of [tex]Cu^{2+}[/tex] cation and [tex]SO_4^{2-}[/tex] anion.
Copper sulphide with molecular formula [tex](CuS)[/tex], the elements are copper and sulphur. It is formed by combination of [tex]Cu^{2+}[/tex] cation and [tex]S^{2-}[/tex] anion.
Look at the activity series and select which two of the following reactions
would happen on their own. (Remember, if the lone element is more active
than the metal in the compound, the lone element will react and replace the
metal in the compound.)
The Activity Series
Most Active
Lithium (Li)
Potassium (K)
Calcium (Ca)
Sodium (Na)
Aluminum (AI)
Zinc (Zn)
Iron (Fe)
Tin (Sn)
Lead (Pb)
(Hydrogen) (H)
Copper (Cu)
Silver (Ag)
Gold (Au)
Least Active
O A. 2Li + ZnBr2 + 2LiBr + Zn
B. 3Ca+ Al2O3 + 2Al + 3Cao
C. Al +3LICI - AlCl3 + 3Li
D. Sn + ZnSe → SnSe + Zn
Answer:
b
Explanation:
because the correct answer
1- The element sodium has an atomic number of 11 and a
mass number of 12.
How many protons does sodium have?
Answer and Explanation:
Sodium has 11 protons.
To know how many protons are in an element on the periodic table, all you have to do is look at the atomic number. The atomic number is the same as the amount of protons.
The amount of protons defines the element, which is why it appears on the element description as the atomic number.
Hope this helps!
#teamtrees #WAP (Water And Plant)
state the difference between isotopes and isobars
Answer:
Isotopes:- these are those elements in which atoms are same but mass number is different. for eg:- 12^C 6.____________________________________________________________________________
Isobars:- these are those elements in which mass number is same but atoms are different. for example:- 2^Ca 18.QUICKKKK How much of the protein consumed by humans around the world is fish? 5 percent 20 percent 40 percent 50 percent
Answer:
20%
Explanation:
I HOPE THIS HELPS YOUUUU
Answer:
20%
Explanation:
FOOD MACROMOLECULES INTRODUCTION
Biological Macromolecules
Most common elements in living things are carbon, hydrogen, nitrogen, and oxygen. These four elements constitute about 95% of your body weight. All compounds can be classified in two broad categories ---organic and inorganic compounds. Organic compounds are all based on carbon. Carbon can form single bonds with another atom and also bond to other carbon molecules forming double and triple bonds. This allows carbon based molecules to form single and double rings, chains, and branching chains. Most organic compounds are built primarily of carbon, hydrogen, and oxygen but in different ratios. Each small organic molecule can be a unit of a large organic molecule called a macromolecule. If the small organic units are identical or form patterns they are called monomers and the large organic molecule they form is called a polymer.
When monomers are joined together the reaction is called dehydration synthesis or condensation as water is produced when the monomers are bonded together. To break the polymers down again the reaction is called hydrolysis. Notice how water is used or produced in these two reactions shown to the right.
There are four classes of macromolecules: carbohydrates, lipids, proteins, and nucleic acids. Heterotrophs, like us, must get these biological macromolecules from our food which we break down into monomers through digestion. This makes the molecules small enough to cross cell membranes. Our cells use them either as energy sources or to build the carbohydrates, proteins, lipids, and nucleic acids that our body needs
Questions:
.
What atom makes up the backbone of biological macromolecules?
Answer:
this is nice..... cool
Explanation:
An isotope becomes more stable by changing the number of what?
HELP!! 75 pts
A 12.00 gram sample of a crude ore contains 2.89 % HgS. What is the percentage of mercury in the ore? (2.49)
The percentage of mercury in the ore : 2.49%
Further explanationGiven
12 g of sample
2.89% HgS
Required
The percentage
Solution
mass of HgS in the ore :
= 2.89% x 12 g
= 0.3468 g HgS
Mass of Hg in HgS :
= (Ar Hg/MW HgS) x mass HgS
= (200.592/232,66 g/mol) x 0.3468
= 0.299 g
% mercury (Hg) in sample(a crude ore) :
= (0.299 g : 12 g) x 100%
= 2.49%
Which reagent is the limiting reagent in a reaction?
A. The one with the largest molar mass
B. The one with the largest coefficient
C. The one with the smallest coefficient D. The one that runs out first in the reaction
Answer:
D. The one that runs out first in the reaction
Explanation:
Limiting reagent is the one that limit the yield of product because of its lower amount and run out first. Lets take an example,
Mass of calcium carbonate = 25 g
Mass of hydrochloric acid = 13.0 g
Mass of calcium chloride produced = ?
Chemical equation:
CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂
Number of moles of CaCO₃:
Number of moles of CaCO₃ = Mass /molar mass
Number of moles of CaCO₃= 25.0 g / 100.1 g/mol
Number of moles of CaCO₃ = 0.25 mol
Number of moles of HCl:
Number of moles of HCl = Mass /molar mass
Number of moles of HCl = 13.0 g / 36.5 g/mol
Number of moles of HCl = 0.36 mol
Now we will compare the moles of CaCl₂ with HCl and CaCO₃ .
CaCO₃ : CaCl₂
1 : 1
0.25 : 0.25
HCl : CaCl₂
2 : 1
0.36 : 1/2 × 0.36 = 0.18 mol
The number of moles of CaCl₂ produced by HCl are less it will be limiting reactant.
Answer:
D. The one that runs out first in the reaction
Explanation:
it was right
The amount of kinetic energy something has depends on its...
A) mass and speed
B) mass and height
C) mass and weight
Answer:
it depends on mass and speed
You have 50 L of CO2 gas at standard temperature and pressure (STP). What would need to be done to the pressure to cut the volume of gas in half?
The pressure is doubled(2 atm)
Further explanationGiven
50 L of CO₂ gas at STP
Required
The pressure
Solution
Changing pressure, constant temperature⇒Boyle's Law
At a fixed temperature, the gas volume is inversely proportional to the pressure applied
[tex]\tt \rm p_1V_1=p_2.V_2\\\\\dfrac{p_1}{p_2}=\dfrac{V_2}{V_1}[/tex]
STP⇒1 atm, T=273 K
The (new) volume of gas in half, so V₂=0.5 V₁ = 0.5 x 50 = 25 L
Because the gas volume is inversely proportional to the pressure than the pressure doubled = 2 atm
Or we can use the formula :
P₂=(P₁V₁)/V₂
P₂=(1 atm x 50 L)/25 L
P₂= 2 atm
PLEASE HELP ME WILL DO ANYTHING ‼️‼️
A fluorine atom has 9 electrons. Draw the Bohr model for fluorine using the pattern you observe for the Bohr models for hydrogen helium, oxygen and neon
Answer:
In first shell 2 electrons are present and 7 electrons are present in last shell
Explanation:
Please help!! I'll mark brainliest! (see the picture below)
Explanation:
Why brunojg driftwood makes colored fire... Burning driftwood, especially from the ocean gets a fire with blue and lavender flames. The colored fire comes from excitation of the metal salts that have soaked I to the wood. While the flames arepretty, the smoke give off of the fire is toxic
A coiled spring with coils that are closely spaced then widely then closely then widely then closely, ending with a yellow line labeled 1 second. What is the frequency of this wave?
Answer:
The frequency of the wave is 2Hz.
Explanation:
The frequency of a wave is the number of waves that pass a fixed point in a given amount of time. It can be measured by counting the number of crests that pass the point in a given time period. The higher the number is, the greater is the frequency of the wave.
So, by counting the number of times the coils in the spring are widely spaced, which is 2 times in 1 second, we get the frequency of the wave.
Answer:
The answer is 2.
Explanation:
Hope this helps ;)
Which ecological level has the most organisms
individual, population, or community?
How do you separate a mixture of sodium chloride and potassium trioxonitrateV
Answer:
See explanation
Explanation:
We separate substances based on their important properties such as reaction to heat, solubility in water, magnetic properties, etc.
To separate sodium chloride and potassium trioxonitrateV, we need to heat the solution. KNO3 dissolves at a high temperature and crystallizes out as the solution is cooled.
Hence when we heat the solution, KNO3 dissolves, as we cool the solution, solid KNO3 crystals are obtained while NaCl remains in solution. We have now separated the two salts in the solution.
Note that the solubility of NaCl is almost independent of temperature.
If F1 = 500 N, what does F equal? PLEASE HELP
Magnetism is always present when electric charges ___________.
Answer:
begin to move
Explanation:
When electric charges begin to move, this is when magnetism takes place.
Hope this helped!
*CHEMISTRY*
An atom was determined to have an electron configuration of 2-5. This atom should have a Lewis dot diagram with....
O 7 dots
O 5 dots
O 2 dots
O 1 dot
96.0 g. of a gas occupies 48.0 L at 700.0 mm Hg and 20.0 °C. What is its molecular weight?
Answer:
I hope this helps 52.2 g/mol
Explanation:
1) Solve for the moles using PV = nRT:
n = PV / RT
n = [(700.0 mmHg / 760.0 mmHg atm¯1) (48.0 L)] / [(0.08206 L atm mol¯1 K¯1) (293.0 K)]
n = 1.8388 mol
2) Divide the grams given (96.0) by the moles just calculated above:
96.0 g / 1.8388 mol = 52.2 g/mol
Molecular weight of the gas is 52.2 g/mol.
What is ideal gas equation?Ideal gas equation is a hypothetical equation which tells about the behavior of the gas under standard condition and it ca be described as:
PV = nRT, where
P = pressure = 700.0 mm Hg (given)
V = volume = 48.0 L (given)
R = universal gas constant = 0.08206 L atm mol¯¹ K¯¹
T = temperature = 20.0 °C = 293 K
On putting theses values in the above equation we get for moles is as:
n = (700 × 48) / (0.08206 × 293) = 1.8 moles
We know that moles can be represented as:
n = W / M, where
W = given weight = 96g
M = molecular weight = to find?
Putting values in the mole equation, we get
M = 96 / 1.8 = 52.2 g/mol
Hence, molecular weight of gas is 52.2 g/mol.
To know more about ideal gas equation, visit the below link:
https://brainly.com/question/1056445
How much heat is required to melt 20 g of gold at 1064.18 °C with a heat of fusion of 64 J/g *
Answer:
1280J are required.
Explanation:
Heat of fusion is defined as the amount of heat required to change its state from liquid to solid at its melting point at constant pressure.
As heat of fusion of gold is 64J/g, there are required 64J to melt 1g of gold at its melting point. The energy required to melt 20g is:
20g * (64J/g) =
1280J are required
*The diagram has to do with the question*
Pls help
1. When a liquid becomes vapor, its gas particles begin to exert...
a. air pressure.
c. vapor pressure.
b. equilibrium pressure.
d. no pressure
Answer:
vapor pressure.
Explanation:
Answer:
I think it is vapor pressure or air pressure