You have 8 red M&Ms, 6 brown M&Ms, 4 yellow M&Ms, and 3 green M&Ms.
What percent of M&Ms are red?
Answer to 1 Decimal Place (Check your rounding)
Answer:
38.1
Explanation:
8+6+4+3=21
8/21
38.1
Rutherfordium-261 has a half-life of 1.08 min. How long will it take for a sample of rutherfordium to lose one-third of its nuclei?
Answer:
[tex]t=1.712min[/tex]
Explanation:
Hello!
In this case, since the radioactive decay equation is:
[tex]\frac{A}{A_0}=2^{-\frac{t}{t_{1/2} }[/tex]
Whereas A stands for the remaining amount of this sample and A0 the initial one. In such a way, since the sample of rutherfordium is reduced to one-third of its nuclei, the following relationship is used:
[tex]A=\frac{1}{3} A_0[/tex]
And we plug it in to get:
[tex]\frac{\frac{1}{3} A_0}{A_0}=2^{-\frac{t}{t_{1/2}} } \\\\\frac{1}{3}=2^{-\frac{t}{t_{1/2}} }[/tex]
Now, as we know its half-life, we can compute the elapsed time for such loss:
[tex]log(\frac{1}{3})=log(2^{-\frac{t}{t_{1/2}} })\\\\log(\frac{1}{3})=-\frac{t}{t_{1/2}} }*log(2)[/tex]
[tex]t=-\frac{log(\frac{1}{3})t_{1/2}}{log(2)} \\\\t=1.71min[/tex]
Best regards!
How many molecules are in 50.0 grams of NaOH?
7.53 × 10²³ molecules NaOH
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 TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
50.0 g NaOH
Step 2: Identify Conversions
Avogadro's Number
Molar Mass of Na - 22.99 g/mol
Molar Mass of O - 16.00 g/mol
Molar Mass of H - 1.01 g/mol
Molar Mass of NaOH - 22.99 + 16.00 + 1.01 = 40 g/mol
Step 3: Convert
Set up: [tex]\displaystyle 50.0 \ g \ NaOH(\frac{1 \ mol NaOH}{40 \ g \ NaOH})(\frac{6.022 \cdot 10^{23} \ molecules \ NaOH}{1 \ mol \ NaOH})[/tex]Multiply: [tex]\displaystyle 7.5275 \cdot 10^{23} \ molecules \ NaOH[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
7.5275 × 10²³ molecules NaOH ≈ 7.53 × 10²³ molecules NaOH
When 1 mole of P4O10(s) reacts with H2O(l) to form H3PO4(aq) according to the following equation, 453 kJ of energy are evolved. P4O10(s) 6H2O(l)4H3PO4(aq)
The question is incomplete, the complete question is;
When 1 mole of P4O10(s) reacts with H2O(l) to form H3PO4(aq) according to the following equation, 453 kJ of energy are evolved.
P4O10(s) + 6H2O(l)When 1 mole of P4O10(s) reacts4H3PO4(aq)
Is this reaction endothermic or exothermic? _________endothermicexothermic
Answer:
The reaction is exothermic
Explanation:
An exothermic reaction refers to any reaction in which heat was EVOLVED. The word was stressed to indicate that it holds the key to answering the question correctly.
We were told in the question that heat was evolved, hence the reaction is exothermic in nature.
The balanced thermochemical equation of the reaction is :
P₄O₁₀(s) + 6H₂O(l) → 4H₃PO₄(aq) ____ ΔH = -453 kJ
Calculate the energy required to heat 179g of ethanol from to . Assume the specific heat capacity of ethanol under these conditions is . Be sure your answer has the correct number of significant digits.
Answer:
9.52 × 10³ J
Explanation:
There is some info missing but I found it on the web.
Calculate the energy required to heat 179g of ethanol from -2.2 °C to 19.6 °C. Assume the specific heat capacity of ethanol under these conditions is 2.44 J/g.°C. Be sure your answer has the correct number of significant digits.
Step 1: Given data
Mass of ethanol (m): 179 gInitial temperature: -2.2°CFinal temperature: 19.6 °CSpecific heat capacity of ethanol (c): 2.44 J/g.°CStep 2: Calculate the temperature change
ΔT = 19.6 °C - (-2.2 °C) = 21.8 °C
Step 3: Calculate the energy required (Q)
We will use the following expression.
Q = c × m × ΔT
Q = 2.44 J/g.°C × 179 g × 21.8 °C
Q = 9.52 × 10³ J
Select the correct answer.
An iron bar at 200°C is placed in thermal contact with an identical iron bar at 120°C in an isolated system. After 30 minutes, both iron bars are at 160°C. If the iron bars were placed in thermal contact in an open system instead of an isolated system, how would the results be different? Assume that the room temperature is 25°C.
A.
The temperatures of the iron bars after 30 minutes would be less than 160°C because heat would be lost to the surroundings.
B.
It would take more than 30 minutes for both iron bars to reach 160°C because heat would be transferred less efficiently.
C.
The temperatures of both iron bars would increase as they absorb heat from the surroundings.
D.
The temperatures of both iron bars would decrease because pieces of them would be lost to the surroundings.
It is not D or C
Pick A or B
Which bonds below are hydrophilic?
A) CC, CH
B) NH, OH, OP, OC
C) NH, OH, OP, OC, CC, CH
I need help asap please help me
12. What is the volume of 0.07 mol of neon gas at STP?
2 L Ne
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Using Dimensional AnalysisSTP (Standard Conditions for Temperature and Pressure) = 22.4 L per mole at 1 atm, 273 KExplanation:Step 1: Define
0.07 mol Ne (g)
Step 2: Identify Conversions
STP - 22.4 L per mole
Step 3: Convert
Set up: [tex]\displaystyle 0.07 \ mol \ Ne(\frac{22.4 \ L \ Ne}{1 \ mol \ Ne})[/tex]Multiply: [tex]\displaystyle 1.568 \ L \ Ne[/tex]Step 4: Check
Follow sig fig rules and round. We are given 1 sig fig.
1.568 L Ne ≈ 2 L Ne
at a particulat temperature, a smaple of pure water has a Kw of 7.7x10-14. what is the hydroxide concentration of this sample
Answer: The hydroxide concentration of this sample is [tex]3.85\times 10^{-7}[/tex]
Explanation:
When an expression is formed by taking the product of concentration of ions raised to the power of their stoichiometric coefficients in the solution of a salt is known as ionic product.
The ionic product for water is written as:
[tex]K_w=[H^+]\times [OH^-][/tex]
[tex]7.7\times 10^{-14}=[H^+]\times [OH^-][/tex]
As [tex][H^+]=[OH^-][/tex]
[tex]2[OH^-]=7.7\times 10^{-14}[/tex]
[tex][OH^-]=3.85\times 10^{-7}[/tex]
Thus hydroxide concentration of this sample is [tex]3.85\times 10^{-7}[/tex]
Consider 55 mL of water (H2O) in a beaker and 55 mL of acetone [(CH3)2CO] in an identical beaker under identical conditions. Complete the sentences to explain the relationship between the vapor pressure of water and acetone.
Answer:
More slowly than
Larger than
Weaker
Explanation:
The vapor pressure of a solution describes how quickly a solution will turn into vapour. If we say that a solution has a high vapour pressure, we are actually saying that the solution turns into vapour more quickly.
Acetone has a higher vapour pressure than water so acetone turns to vapour quicker than water.
Vapour pressure has a lot to do with the magnitude of intermolecular forces in solution. The stronger the magnitude of intermolecular forces, the lower the vapor pressure and the more slowly the solution evapourates.
So, the hydrogen bonds in water provides stronger intermolecular forces than dispersion and dipole interaction in acetone. Hence, water vaporizes more slowly than acetone.
What is hydrophilic.
Answer:
of, relating to, or having a strong affinity for water
Explanation:
Answer:
water loving or havin affection for water, not like hydrophobic wich is fear of water or not resistant to water
Explanation:
please help !!!
What law states that matter can never be created or destroyed?
A. The law of gravity
B. The law of constant phases
C. The law of conservation of matter
D. The atomic theory
Answer:
C) The law of conservation of matter
Explanation:
Conservation means keeping/ retaining something, in this case it is matter. Hope this helps!
Calculate the mass, in grams, of 1.2000 mol Mg₃N₂
The type of elements found in groups 13-18 include
Answer:
Please put question in!
Explanation:
How many atoms are in 5 moles of Cadmium?
3 × 10²⁴ atoms Cd
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
5 mol Cd (Cadmium)
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
Set up: [tex]\displaystyle 5 \ moles \ Cd(\frac{6.022 \cdot 10^{23} \ atoms \ Cd}{1 \ mol \ Cd})[/tex]Multiply: [tex]\displaystyle 3.011 \cdot 10^{24} \ atoms \ Cd[/tex]Step 4: Check
Follow sig fig rules and round. We are given 1 sig fig.
3.011 × 10²⁴ atoms Cd ≈ 3 × 10²⁴ atoms Cd
Draw a Lewis structure for C2H3Cl . Include all hydrogen atoms and show all unshared electron pairs. None of the atoms bears a formal charge, and all atoms have octets (except for hydrogen atoms, which have duets).
Answer:
See attached picture.
Explanation:
Hello!
In this case, since C2H3Cl is an organic compound we need a central C-C parent chain to which the three hydrogen atoms and one chlorine atom provides the electrons to get all the octets except for H as given on the statement.
In such a way, on the attached picture you can find the required Lewis dot structure without formal charges and with all the unshared electron pairs, considering there is a double bond binding the central carbon atoms in order to compete their octets.
Best regards!
The lewis structure of given molecule is given below. Carbon has 4 electron. out of which electron make bond with carbon and one with hydrogen and chlorine.
If the compound's molecular formula is known, electron dot structures or Lewis dot formulas can be drawn. It describes the type of bond and the placement of the atoms within the molecule that are joined together. In homage of American chemist Gilbert Newton Lewis, molecules are depicted as having a Lewis electron dot structure or simply a Lewis structure. The lewis structure of given molecule is given below.
To know more about lewis structure, here:
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Which branch of chemistry would be used to make steel?
Answer:
the five major branches of chemistry are organic, inorganic, analytical, physical, and biochemistry.
A pitcher throws a ball and it reaches home plate 60 ft away in 0.41
seconds. What is the approximate speed of the ball?
O 100 ft/s
50 ft/s
O 146 ft/s
0 24.6 ft/s
Answer:
The answer is 146.
Explanation:
To calculate speed, you have to divide the distance by the time. So, 60/0.41 would be approximately 146.
54 is the atomic number for ?Xe.
Answer:
Xenon
Atomic Number: 54
Explanation:
Periodic Table
Answer:
Xenon
Explanation:
Xenon is a chemical element with symbol Xe and atomic number 54.
50 POINTS PLEASE NO FAKE ANSWERS I REALLY NEED THESE ANSWERED
1. The following reaction shows calcium chloride reacting with silver nitrate.
CaCl2 + 2AgNO3 → 2AgCl + Ca(NO3)2
How many grams of AgCl are produced from 30.0 grams of CaCl2?
(Molar mass of Ca = 40.078 g/mol, Cl = 35.453 g/mol, O = 15.999 g/mol, Ag = 107.868 g/mol, N = 14.007 g/mol)
19.4 grams
38.8 grams
58.2 grams
77.5 grams
2. The table shows the recipe and the available ingredients for making the maximum possible number of sandwiches.
Making Sandwiches
Recipe for One Sandwich Ingredients Available
2 cheese slices, 1 ham slice, 2 bread slices 12 cheese slices, 10 ham slices, 12 bread slices
If the ingredients represent reactants of a chemical reaction, which of the following represents the leftover reactant?
Two ham slices
Four ham slices
Two cheese slices
Four cheese slices
3. Read the given chemical reaction.
C2H6 + O2 → CO2 + H2O
How many moles of H2O are produced during the complete combustion of 1.4 moles of C2H6?
2.8 moles
4.2 moles
5.6 moles
7.0 moles
4. The image represents the reaction between a certain number of molecules of N2 and H2.
[IMAGE INCLUDED]
If the maximum possible amount of NH3 is formed during the reaction, what is the leftover reactant?
One molecule of N2
One molecule of H2
Two molecules of N2
Two molecules of H2
1. Matter can (change form/be created)
Answer: Yes
Explanation:
Duh it can change. Because matter is what we are made of, and if we change, then matter also changes along with us :)
I NEED APPROPRIATE ANSWERS SO IF ANYONE CAN PLEASE ANSWER THESE TWO QUESTIONS I WILL GIVE YOU BRAINIEST. Can someone please help me with these two questions:
What happens when PURE sodium (Na) and water react?
12. What happens when sodium chloride (NaCl or table salt) mixes with water? Is it the same or different when PURE sodium reacts with water?
Answer:
1. When salt is mixed with water, the salt dissolves because the covalent bonds of water are stronger than the ionic bonds in the salt molecules
2. Pure sodium explodes on contact with water
Explanation:
You are given 100 mL of of a KOH solution with pH of 12.0. You are required to change the pH to 11.0 by adding water. How much water will you add
Answer:
We need to add 900 mL of water.
Explanation:
To know the amount of water to add first we need to calculate the concentration of KOH when the pH is 12 and when is 11:
[tex] 14 = pH + pOH [/tex]
[tex] pOH = -log[OH] [/tex]
[tex] OH = 10^{-pOH} [/tex]
When pH = 12 (initial):
[tex]pOH_{i} = 14 - 12 = 2[/tex]
[tex]OH_{i} = 10^{-2}=0.01 M[/tex]
When pH = 11 (final):
[tex]pOH_{f} = 14 - 11 = 3[/tex]
[tex]OH_{f} = 10^{-3} = 0.001 M[/tex]
Now, by using the following equation we can find the volume of the solution to achieve a pH = 11:
[tex]C_{i}V_{i} = C_{f}V_{f}[/tex]
[tex]V_{f} = \frac{C_{i}V_{i}}{C_{f}} = \frac{0.01 M*100 mL}{0.001 M} = 1000 mL[/tex]
Finally, to bring 100 mL of the initial solution to 1000 mL we need to add the following amount of water:
[tex]1000 mL = V_{KOH} + V_{H_{2}O}[/tex]
[tex] V_{H_{2}O} = 1000 mL - V_{KOH} [/tex]
[tex] V_{H_{2}O} = 1000 mL - 100 mL = 900 mL [/tex]
Therefore, we need to add 900 mL of water.
I hope it helps you!
The amount of water that needs to be added will be 900 mL
What will be the amount of water needed?For finding the amount of water added we have to calculate the concentration of KOH at pH=12 and pH=11
[tex]14=pH+_pOH[/tex]
[tex]_pOH=-Log[OH][/tex]
[tex]OH=10^{-_pOH}[/tex]
[tex]_pOH_f=14-11=3[/tex]
When pH = 12 (initial):
[tex]_pOH_i=14-12=2[/tex]
[tex]_pOH_i=10^{-2}=0.01[/tex]
When pH = 11 (final):
[tex]_pOH_i=10^{-2}=0.01[/tex]
[tex]_pOH_f=14-11=3[/tex]
Now, by using the following equation we can find the volume of the solution to achieve a pH = 11:
[tex]C_iV_i=C_fV_f[/tex]
[tex]V_f=\dfrac{C_iV_I}{C_f} =\dfrac{0.01\times100}{0.001} =1000\ mL[/tex]
Finally, to bring 100 mL of the initial solution to 1000 mL we need to add the following amount of water:
[tex]1000=V_{KOH}+V_{H_2O}[/tex]
[tex]V_{H_2O}=1000mL-V_{KOH}[/tex]
[tex]V_{H_2O}=1000-100=900mL[/tex]
Thus the amount of water that needs to be added will be 900 mL
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Which is the following is true about the properties of the mantle?
The mantle produces magnetic fields.
The mantle is hotter the core.
The mantle contains two different layers.
There are rock samples collected from the mantle.
Answer:
it's the 2 I'm pretty sure
Explanation:
please give me a heart
Answer:
Explanation:
sd dsf sd f sdf sdf
Which of the following is a true statement?
All flat-topped hills are plateaus.
Volcanoes form all flat-topped hills.
All flat-topped hills are mesas.
Flat-topped hills can either be plateaus or mesas.
Answer:
D Flat Top Hills Can Be Plateaus or mesas
Explanation:
20g of water at 30°C was mixed with 40g of water at 75°C. What is
the final temperature of the mixture? (specific heat capacity of water
is 4.184 J/g°C).
Answer:
The temperature of the mixture is 60°C
Explanation:
We can write the energy of water as follows:
E = m×C×T
Where E is energy in Joules, m is mass of water, C is specific heat of water = 4.184J/g°C and T is temperature
Replacing fot both samples:
E = 20g×4.184J/g°C×30°C
E = 2510.4J
E = 40g×4.184J/g°C×75°C
E = 12552J
The total energy of the mixture is 12552J + 2510.4J = 15062.4J
Mass = 60g:
15062.4J = 60g×4.184J/g°C×T
60°C = T
The temperature of the mixture is 60°CHCl, NaCl, and CO are all examples of chemical
properties
bonds
formulas
changes
Answer:
HCL, NACL and CO are the examples of chemical formulas
if mixture didn't exist how would life be different
Answer:
boring
Explanation:
life would be meaningless like everyone being like on person
is sodium a mixure or substance
Answer:
it is a substance
Explanation:
because sodium is an element which its consistent is only sodium atom