Answer:
it was invented in 1960
Explanation:
it was descibed as a wooden instrument ideally suited for gravity programmes in areas of limited latitude and temperature variations
Which of these is true for natural selection but not artificial selection?
A.Humans choose specific organisms to reproduce.
B.Competition for resources determines reproductive success.
C.Unfavorable traits decrease in frequency in a population.
D.Genetic engineering introduces new traits into a population.
Answer:
B
Explanation:
If 0.654 g of oxygen dissolves in 1.5 L of water at 1.65 atm, at what pressure (in atm) would you be able to dissolve 1.35 g in the same amount of water?
Explanation:
dylalove464
06/11/2020
Hello,
In this case, we first compute the moles of oxygen in 0.654 g and 1.35 g by using its molar mass (32 g/mol):
Then, by using the ideal gas equation at the both states, given the same both temperature and volume:
We compute the volume at the second moles:
Best regards.
Answer:
3.41
Explanation:
:)
Which has more molecules in it 10g H, 0 or 10g NaCl*
A)010g of H0
B)10g of NaCl
C)They have the same number of molecules
D)Cannot be determined
Answer:
10 grams of hydrogen
Explanation:
Find the area of the sector with a central angel of 120 and a radius of 8 inshces. Leave in terms of pie
Answer:
A = 66.98 square in.
Explanation:
The Area of a sector is given by the formula
[tex]A = \frac{\theta}{360}\times \pi r^2[/tex]
here θ is the central angle and r is the radius
given that θ = 120° and radius = 8 inches
[tex]A = \frac{120}{360}\times3.14\times 8^2[/tex]
A = 66.98 square in.
2. Which element below would be the best choice when creating a covalent molecule with an
Oxygen atom?
A. Na
B. Mg
C. Ne
D. O
Which atom attracts electrons most strongly? br F Rb
Fluorine has the highest electronegativity in comparison to other elements therefore, the F atom attracts electrons most strongly.
What is electronegativity?The electronegativity of an atom measures the tendency of an element to attract the bonded electrons pairs towards itself. The electronegativity of an atom is determined with respect to another bonded atom.
Electronegativity can be described as a chemical property of an atom or a functional group to attract electrons toward itself. The electronegativity of an atom depends on the atomic number and the distance of valence electrons from the charged nuclei.
When two different atoms are bonded through a bond. More electronegative will attract the electron density of the bond towards itself.
As we know, the electronegativity decreases as we move down the group in the periodic table. Fluorine is the most electronegative element in the periodic table therefore, Fluorine (F) will attract the electrons toward it most strongly.
Learn more about electronegativity, here:
brainly.com/question/17762711
#SPJ6
A certain atom has a mass of 16 and an atomic number of 7. What element is this ?
Answer:
Nitrogen
Explanation:
According to the Periodic Table, the atom with a mass is 16 but the Atomic number is 7 for Nitrogen. That means that Nitrogen is an isotope.
Witch part of an atom is mostly empty space?
Will these magnets attract or repel?
Attract
Repel
Answer:
repel, if you stick them together as they are, because the north and south poles are next to each other
Explanation:
If the half life of iridium-182 is 15 years, how much of a 3 gram sample is left after 2 half-lives?
A) .57 grams
B) .70 grams
C) 2.25 grams
D) .75 grams
Answer:
D. 0.75 grams
Explanation:
The data given on the iridium 182 are;
The half life of the iridium 182, [tex]t_{(1/2)}[/tex] = 15 years
The mass of the sample of iridium, N₀ = 3 grams
The amount left, N(t) after two half lives is given as follows;
[tex]N(t) = N_0 \left (\dfrac{1}{2} \right )^{\dfrac{t}{t_{1/2}} }[/tex]
For two half lives, t = 2 × [tex]t_{(1/2)}[/tex]
∴ t = 2 × 15 = 30
[tex]\dfrac{t}{t_{(1/2)}} = \dfrac{30}{15} = 2[/tex]
[tex]\therefore N(t) = 3 \times\left (\dfrac{1}{2} \right )^2 = 0.75[/tex]
∴ The amount left, N(t) = 0.75 grams
Al2S3 + 6H20 + 2Al(OH)2 + 3H2S
How many TOTAL number mole to mole ratios will there be total?
Answer:
the correct answer is 23:19
The formula for calclum chloride Is CaCl2. Which argument best describes the type of chemical bond that was formed between the calcium and chlorine atoms? An lonic bond because calcium is sharing its electrons with the chlorine. A covalent bond because calclum is transferring its electrons to the chlorine. A covalent bond because calcium is sharing its electrons with the chlorine. An lonic bond because calcium is transferring Its electrons to the chlorine.
Answer:
An lonic bond because calcium is transferring Its electrons to the chlorine.
Explanation:
Metals usually form compounds with non-metals through ionic bonding.
Metals are electropositive elements which form ions by the loss of electrons, whereas non-metals are electronegative elements which form ions by the gain of electrons.
Compounds are formed when two or more elements combine together. The formation of compounds involves formation of bonds which may be either ionic or covalent bonds.
The type of bonding that exists between the a metallic calcium atoms and non-metallic chlorine atoms in calcium chloride, CaCl₂, is ionic bonding. In the process of formation of the compound, calcium atoms which have a valency of 2 readily donates their two valence electrons to chlorine atoms to form calcium ions, Ca²+. Each chlorine atoms having a valency of 1 accepts an electron to form chloride ions Cl-. Two chlorine atoms accept the two electrons donated by a calcium ion. Due to strong electrostatic forces of attraction between the calcium ion and the two chloride ions, the ionic compound CaCl₂ is formed.
Additional Activities
Direction: Sharpen your understanding in projectile motion. Calculate the maximum height reached and the horizontal range of the given launched angles and initial velocity of a projectile. You may opt to use the Projectile Motion Simulation with Air Friction by AERDEMIR which can be downloaded via Play Store for free.
1. To use the simulator, set the given values as shown in the left.
Start Angle = Launched Angle = refer to the table Start Velocity = Initial Velocity = 20 m/s
Change the gravitational acceleration to 9.8 only Delete the values in Air Density and Drag Coefficient
2. Deactivate the friction force by tapping the icon indicated in the above image.
The maximum height of an object, given the initial launch angle and initial velocity is found with:
h = v2 is in2θi 2g
h = v i 2 sin 2 θ i 2 g.
How would the balloons interaction with each other change if the balloons were moved further apart? Explain.
Explanation:
It is known that like charges repel each other and unlike charges attract each other.
As the balloons are facing each other with like charges so they will repel each other. Hence, they will move apart.
But when balloons were moved further apart then interaction between them will decrease and then there will be no force of repulsion or force of attraction.
What is the mass percentage of copper in a 250 g sample of brass. Brass is made of copper and zinc and copper content of the sample is 150 g
Answer:
Percentage of copper in sample = 60%
Explanation:
Given:
Mass of copper = 150 gram
Mass of brass = 250 gram
Find:
Percentage of copper in sample
Computation:
Percentage of copper in sample = [Mass of copper / Mass of brass]100
Percentage of copper in sample = [150/250]100
Percentage of copper in sample = [0.6]100
Percentage of copper in sample = 60%
Write a nuclear equation for the beta decay of Promethium-165
Answer:
see your answer in pic
Explanation:
There can be emissions of radiations like gamma radiation. There can be emission of particles too like alpha particle. Therefore, the nuclear equation for the beta decay of Promethium-165 is
¹⁶⁵Pm[tex]\rightarrow[/tex]⁰e₋₁ + ₆₂Sm¹⁶⁵
What is nuclear decay?Nuclear decay is process in which the radioactive element releases particles or radiations. Alpha particles is ⁴₂He. Alpha particle is nothing but helium particle. The kinetics that is related to nuclear decay is of first order.
The nuclear equation for the beta decay of Promethium-165 is
¹⁶⁵Pm[tex]\rightarrow[/tex]⁰e₋₁ + ₆₂Sm¹⁶⁵
Beta decay of Promethium-165 is the emission of electron particle from the given isotope. the product is Samarium ₆₂Sm¹⁶⁵.
Therefore, the nuclear equation for the beta decay of Promethium-165 is
¹⁶⁵Pm[tex]\rightarrow[/tex]⁰e₋₁ + ₆₂Sm¹⁶⁵
To know more about nuclear decay, here:
https://brainly.com/question/21114779
#SPJ2
Potassium (K):
g/mol?
CH4 + O2 → CO2 + H2O what is the balacnced chemical reaction
Answer:
The combustion of methane or octane is exothermic; it releases energy. CH4 + 2 O2 → CO2 + 2 H2O + energy The energies of the products are lower than the energiies of the reactants
A neutron collides with a nitrogen atom, resulting in a transmutation. Balance the equation.
on + '
NX+1H
Identify the unknown product by identifying the unknown letters.
Ais
Z is
X is
Answer:
The answer is ¹³₆C
Explanation:
searched it up
What can a nation do to improve the exchange rate of its currency?
A.
try to improve its balance of trade
B.
try to decrease its trade surplus
C.
try to lower its gross domestic product (GDP)
D.
try to export less while importing more
Answer:
A
Explanation:
balance the trades and improving them
Answer:
A:try to improve it's balance of trade
Explanation:
Vhon Anadome
Atomic nucleus questions
Which of the following decay processes results in the largest change in mass of a nucleus?
Choose 1 answer:
А
Beta decay
Gamma decay
Neutron emission
D
Alpha decay
Answer:
d
Explanation:
Name two types of silk
Answer:
Tussar silk
Charmeuse
Explanation:
Hope this helps! :)
sources of magnesium to plants
Calculate weight of anhydrous compound from remains upon dehydration of 2g copper sulphate pentahydrate
Answer:
1.28 g
Explanation:
Mass of anhydrous compound/molar mass of anhydrous compound = mass of hydrated compound/ molar mass of hydrated compound
Mass of anhydrous compound = ?
Mass of hydrated compound = 2g
Molar mass of anhydrous compound= 160 g/mol
Molar mass of hydrated compound = 250 g/mol
x/160 = 2/250
250x = 2 ×160
x= 2 × 160/250
x= 1.28 g
PLEASE HELP ME PLEASE PLEASE NOW
Answer:
the amount of trials in an experiment
A test light with an electrical resistance of 9.00 S2 draws a current of 1.50 A when
it is connected to an electrical source. How much power does the light use?
Answer:
20.25 W
Explanation:
Applying,
P = I²R.................... Equation 1
Where P = Power, I = current drawn by the test light, R = Resistance of the test light
From the question,
Given: I = 1.5 A, R = 9.00 Ω
Substitute these values into equation 1
P = (1.5²)(9)
P = 2.25×9
P = 20.25 W
Explain why rubbing an alkali like bicarbonate of soda onto an acidic bee sting can ease the pain ?
How many moles are in 4.01x10^24 particles?
Answer:
6.64
Explanation:
so moles
[tex] \frac{number \: of \: \: particles \: }{6.02 \times {10}^{23} } [/tex]
then do =4.01×10^24/6.02×10^23
you get the answer as 6.6445 u only need to write the answer to
3.S.F 6.64 moles
hope this make sense :)
NEED HELP ASAP PLEASE
Identify the type of bonding, covalent, ionic, or metallic, between
the atoms in an oxygen molecule.
Answer:
here hope it helps
Explanation:
covalent bonds
Read the following graduated cylinder.
How many ML?
Answer:
12.8 mL
Explanation:
the bolded bar indicates a count of 5. counting from there would add up to 8/10ths of a mL.
