Answer:
Environmental Changes
Explanation:
Over time, a species will adjust to the changes in environment in order to survive.
Answer:
The correct answer is B, random mutations
Explanation:
Alleles are shuffled in the offspring when random mating, fertilization, and recombination between homologous chromosomes during meiosis occur.
I also took the quiz, Good luck! \ (•◡•) /
Explain why the strength of a polycrystalline metal at room temperature decreases as its grain size increases.
Answer:
Metals with larger grains have less grain-boundary area per unit volume, and hence will not be as able to generate as many entanglements at grain boundaries, thus the strength will be lower.
Which of these organisms is considered the most complex?
squid
whale
spider
ladybug
A container holds one mole of a gas if the amount of gas is tripled how many molecules of gas will be in the container?
Answer:At the molecular level, the pressure of a gas depends on the number of collisions its molecules have with the walls of the container. If the pressure on the piston is doubled, the volume of the gas decreases by one-half. The gas molecules, now confined in a smaller volume, collide with the walls of the container twice as often and their pressure once again equals that of the piston.
Explanation:
Answer:
thanks
Explanation:
What is the noble gas configuration of sulfur
Weathering is a process in the rock cycle. How does weathering contribute to the
formation of rocks?
Answer:
Forces like wind and water break down rocks through the processes of weathering and erosion. ... Forces like wind and water move the rock pieces. They mix with matter like sand to become sediment. Weathering and erosion help shape Earth's surface.
Explanation:
soil is formed from
A. ancestors
B. offspring
C. Parent material
D. recipe
If your grandparents started an account that does not gain interest for you when you were ten with $100 in it. Then when you were fifteen it had $1925. When you were twenty it had $3,750. Demonstrate how much your grandparents are putting in the account
Answer:
each year they are adding £31.25 to the bank account as £31.25 =£375 and times by 5 is £1875 but i did not include the $100 at the beginning
Explanation:
I’ve missed this question twice now. Please help
Answer:
then it only gotta be 2 other options .
Explanation:
The half-life of sodium-24 is 15 days. A laboratory technician measures out a 72 g sample. Approximately how many grams of sodium-24 would remain after 45 days?
Answer:
after 45 days 9 g left
Explanation:
Given data:
Half life Na-24 = 15 days
Mass of sample = 72 g
Mass remain after 45 days = ?
Solution:
Number of half lives passed:
Number of half lives = time elapsed / half life
Number of half lives = 45 days / 15 days
Number of half lives = 3
At time zero total amount = 72 g
After first half life = 72 g/ 2= 36 g
At 2nd half life = 36 g/2 = 18 g
At 3rd half life = 18 g/2 = 9 g
Thus after 45 days 9 g left.
Aqueous sulfuric acid H2SO4 reacts with solid sodium hydroxide NaOH to produce aqueous sodium sulfate Na2SO4 and liquid water H2O. What is the theoretical yield of sodium sulfate formed from the reaction of 75.5g of sulfuric acid and 105.g of sodium hydroxide
Answer:
109.34 g
Explanation:
2NaOH(aq) + H2SO4(aq) ------> Na2SO4(aq) + 2H2O(l)
Number of moles of NaOH = 105g/40g/mol = 2.6 moles
From the reaction equation;
2 moles of NaOH yields 1 mole of sodium sulphate
2.6 moles of NaOH yields = 2.6 × 1/2 = 1.3 moles of sodium sulphate
Number of moles of H2SO4= 75.5g/98 g/mol = 0.77 moles
From the reaction equation;
1 mole of H2SO4 yields 1 mole of sodium sulphate
Hence, 0.77 moles of H2SO4 yields 0.77 moles of sodium sulphate
So H2SO4 is the limiting reactant.
Theoretical yield = number of moles × molar mass
= 0.77 mol ×142 g/mol
= 109.34 g
How many moles are in 6.3 x 10^22 molecules of H3PO4?
0.10 mol H₃PO₄
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
6.3 × 10²² molecules H₃PO₄
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
Set up: [tex]\displaystyle 6.3 \cdot 10^{22} \ molecules \ H_3PO_4(\frac{1 \ mol \ H_3PO_4}{6.022 \cdot 10^{23} \ molecules \ H_3PO_4})[/tex]Multiply: [tex]\displaystyle 0.104616 \ moles \ H_3PO_4[/tex]Step 4: Check
Follow sig fig rules and round. We are given 2 sig figs.
0.104616 mol H₃PO₄ ≈ 0.10 mol H₃PO₄
Draw the Lewis structure for the polyatomic nitrate anion. Be sure to include all resonance structures that satisfy the octet rule.
Answer:
See explanation and image attached
Explanation:
A poly atomic ion refers to an ion that has more than one atom. The nitrate ion is one of such! It contains three oxygen atoms and one nitrogen atom.
It is an ion in which there is charge separation as shown in the image attached to this answer. The structures shown are the Lewis structure of the nitrate ion that satisfy the octet rule.
40. What is the mass of 3 moles of H 2 O
Answer:
54g
Explanation:
Given parameters:
Number of moles of H₂O = 3 moles
Unknown:
mass of water = ?
Solution:
To solve this problem, we use the expression below:
mass = number of moles x molar mass
Molar mass of H₂O = 2(1) + 16 = 18g/mol
Mass of water = 3 x 18 = 54g
What rules should you follow when adding and subtracting? Check all that apply.
Answer:
The answer to this question would be:
2. The exponents need to be the same so the leading numbers can be added or subtracted.
3. The result has the same number of decimal places as the least precise number.
The exponent is the 10^x that used in scientific notation. .When adding 12.3* 10^5 with 34.56 * 10^4, you need to make the exponent same first. In this case, it would become 12.3* 10^5 + 3.456 * 10^5= 15.756* 10^5
The decimal place could be rounded up to the least precise number. I'm not sure with the significant figures but it seems to use the biggest one.
Explanation:
https://brainly.com/question/7413247
Touching a hot stove or the melting of ice in your hand (as you squeeze it) is an example of
Answer: conduction
Explanation:
the heat passes out of the stove and into your hand. So is holding an ice cube – the heat is conducted out of your hand, and into the ice cube (that’s why your hand feels cold).
Answer:
Conduction
Explanation:
Conduction occurs when objects touch. The heat from the warmer object is transferred to the cooler object, eventually evening out the temperatures.
what volume will 2 moles of nitrogen occupy at 780 torr and 10C.
The volume : V = 45.22 L
Further explanationGiven
Moles = n = 2
Pressure = P = 780 torr = 1,02632 atm
Temperature = T = 10 + 273 = 283 K
Required
Volume
Solution
Ideal gas law : PV = nRT
where
P = pressure, atm
V = volume, liter
n = number of moles
R = gas constant = 0.08206 L.atm / mol K
T = temperature, Kelvin
Input the value :
V = (nRT)/P
V = (2 x 0.082 x 283)/1,02632
V = 45.22 L
A sample of lead (Pb) has a volume of 5 cm3 and a mass of 56.5 g. What is
the density of lead?
Hey there!
The formula for density is d = m/v.
The mass of the sample is 56.5 g, and the volume of the sample is 5 cm³.
So, to plug these values into the equation, we have:
[tex]d=\frac{56.5}{5}[/tex]
Simplified, this is:
d = 11.3
The unit for this is g/cm³, or grams per cubic centimeter.
So, the density of lead is 11.3 g/cm³.
Hope this helps!
Answer:
11.3 g/cm³
Explanation:
Density of lead
= Mass / Volume
= (56.5 g) / (5 cm³)
= 11.3 g/cm³
What would be the mass of 9.03 x 10^21 molecules of hydrobromic acid?
1.21 g HBr
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Compounds
Writing CompoundsAcids/BasesAtomic Structure
Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
9.03 × 10²¹ molecules HBr
Step 2: Identify Conversions
Avogadro's Number
Molar Mass of H - 1.01 g/mol
Molar Mass of Br - 79.90 g/mol
Molar Mass of HBr - 1.01 + 79.90 = 80.91 g/mol
Step 3: Convert
Set up: [tex]\displaystyle 9.03 \cdot 10^{21} \ molecules \ HBr(\frac{1 \ mol \ HBr}{6.022 \cdot 10^{23} \ molecules \ HBr})(\frac{80.91 \ g \ HBr}{1 \ mol \ HBr})[/tex]Multiply/Divide: [tex]\displaystyle 1.21325 \ g \ HBr[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
1.21325 g HBr ≈ 1.21 g HBr
A conductor allows heat to flow easily while an insulator
Answer:
an insulator is a substance that does not readily allow the passage of heat or sound.
Explanation:
Nitrogen-13 has a half-life of about 10 minutes. How much of a 320g sample of N-13 would remain after 40 minutes?
Answer:
The half-life of a radioisotope describes the amount of time it takes for said isotope to decay to one-half the original amount present in the sample.
Nitrogen-13, because it has a half-life of ten minutes, will experience two half-lives over the course of the twenty minute period. This means that 25% of the isotope will remain after this.
0.25 x 128mg = 32mg
32mg of Nitrogen-13 will remain after 20 minutes.
The food web above shows how energy moves through a lake environment. If a chemical company were to put a harmful chemical
that kills off all of the phytoplankton, which animal would be immediately affected?
A)bacteria
B)invertebrates
C)human
D)prey fish
Answer:
B: Invertebrates
Explanation:
Since no other food source for invertebrates is shown, the invertebrates will starve and die off first
A compound is composed of only C, H, and O. The combustion of a 0.519-g sample of the compound yields 1.24 g of CO2 and 0.255 g of H2O. What is the empirical formula of the compound
Answer:
C4H4O
Explanation:
1.24 g x 1mol/(44)g = 0.03mol C;
Mass of C: 0.03mol x 12.g/1mol
= 0.36g of C
mol of H: 0.255g x 1mol /(18) x2= 0.028mol
Mass of H; = 0.028g × 1 of H
Mass of O: 0.519 g – (0.36g +0.028g)= 0.131g;
0.131g/16 =0.008 mol
Divide by the smallest number of moles;
0.028/0.008 mol = 3.5; 0.03/0.008 mol =3.75, 0.008 mol/0.008 mol =1
C4H4O
Which of the following is an expression of Boyle's law?
A. PT= constant
B. P/T=constant
C. V/T=constant
D. PV=constant
The expression of Boyle's law is to be considered as the PV=constant.
Hence, the option d is correct.
What is Boyle's law?
In physics, the volume of the gas at a similar kind of temperature should changed oppositely along with the pressure that should be exterted on it.
Also, the expression be like
P1V1 = P2V2
hence, The expression of Boyle's law is to be considered as the PV=constant.
Hence, the option d is correct.
learn more about law here: https://brainly.com/question/14696622
Write a balanced equation for the double-replacement precipitation reaction described, using the smallest possible integer coefficients. A precipitate forms when aqueous solutions of silver(I) nitrate and magnesium sulfate are combined.
Answer: [tex]2AgNO_3(aq)+MgSO_4(aq)\rightarrow Ag_2SO_4(s)+Mg(NO_3)_2(aq)[/tex]
Explanation:
A double displacement reaction is one in which exchange of ions take place. The salts which are soluble in water are designated by symbol (aq) and those which are insoluble in water and remain in solid form are represented by (s) after their chemical formulas.
A double displacement reaction in which on e of the product is formed as a solid is called as precipitation reaction.
The balanced chemical equation is:
[tex]2AgNO_3(aq)+MgSO_4(aq)\rightarrow Ag_2SO_4(s)+Mg(NO_3)_2(aq)[/tex]
10. How do scientific investigations advance scientific knowledge?
Help please
Answer:
Technology used to gather data enhances accuracy and allows scientists to analyze and quantify results of investigations. Scientific explanations emphasize evidence, have logically consistent arguments, and use scientific principles, models, and theories
Explanation:
How can volcanic eruptions be beneficial?
Volcanoes can produce oxygen in the atmosphere.
Volcanoes provide energy for plants and animals to use.
Volcanoes can produce landmass such as islands.
Volcanoes provides homes for certain species of animals and plants.
Answer:
Volcanoes can produce oxygen in the atmosphere.
Explanation:
how does the structure of each passage help determine the content of the passage?
a. Passage I contains a character study, but Passage 2 focuses more on concepts.
b. Passage 2 contains significant cultural information, but Passage 1 illustrates history.
c. Passage 1 explains a scientific phenomenon,
but Passage 2 is purely fictional.
d. Passage 2 describes ongoing action, but
Passage 1 focuses more on feelings.
The answer to the question is a. Passage I contains a character study, but Passage 2 focuses more on concepts.
for all who were wondering
Decide which element probably forms a compound with hydrogen that has a chemical formula most and least similar to the chemical formula of the compound formed by hydrogen and oxygen.
The question is incomplete, the complete question is shown in the image attached to this answer
Answer:
Most similar - sulphur
least similar- gallium
Explanation:
The compound formed when hydrogen reacts with oxygen is water. The chemical formula of water is H2O.
Water is very similar to H2S which is the compound formed when hydrogen reacts with sulphur. The bonds in water and H2S are both polar covalent bonds.
However, gallium is a metal and its hydride (GaH3) is least similar to water.
an ionic bond forms between a ______ and a _____
Suppose a psychrometer reads 80°F for the dry bulb and 76°F for the wet bulb. What is the relative humidity?
Answer: 84%
Explanation:
Using the table attached, one can find out the Relative humidity.
Look at the intersection between the temperature on the dry bulb and the difference between the temperature on the dry and wet bulb.
Dry bulb temperature = 80°F
Wet bulb temperature = 76°F
Difference = 80 - 76 = 4°F
Relative humidity is therefore:
= 84%