Answer:
1: The speculation that continents might have 'drifted' was first put forward by Abraham Ortelius in 1596. The concept was independently and more fully developed by Alfred Wegener in 1912, but his hypothesis was rejected by many for lack of any motive mechanism. 2: The most obvious evidence for continental drift is that the continents appear to fit together like pieces of a puzzle. But scientists were skeptical , and Wegener needed additional evidence to support his hypothesis. Glaciers covered large areas that are now parts of these continents.
Answer:
1. D
2. C
Explanation:
1. Although now accepted, the theory of continental drift was rejected for many years, with evidence in its favor considered insufficient. One problem was that a plausible driving force was missing. A second problem was that Wegener's estimate of the speed of continental motion, 250 cm/year, was implausibly high.
2.The most obvious evidence for continental drift is that the continents appear to fit together like pieces of a puzzle. But scientists were skeptical , and Wegener needed additional evidence to support his hypothesis. Glaciers covered large areas that are now parts of these continents.
Which of the following requires more energy then they produce?
Exothermic
Endothermic
(the subject is science but it wasn’t an option)
Answer:
The answer is endothermic
whoever answers first will get brainliest! this is times so pls help!
You are titrating a 125 mL sample of KOH solution; the pH meter reads 7.00 after the addition of 84.7 mL of 0.750 M HNO3.
What is the concentration of the KOH solution?
A. 0.125 M KOH
B.0.750 M KOH
C.0.508 M KOH
D. 0.0635 M KOH
thanks so much!
By February of 1861, how many states seceded from the Union?
5
11
9
7
Answer:
D. 7
Explanation:
i did it
a train is climbing a gradual hill. the weight of the train creates a downhill force of 150,000 newtons. friction creates an additional force of 25,000 newtons acting in the same direction (downhill). how much force does the train's engine need to create so the train is going uphill at a constant speed?
Answer:
25000 is the answer
Explanation:
The answer is 25000 hope this helps you
25,000N is the total force, the train's engine need to create so the train is going uphill at a constant speed.
What is force?A force in physics is an effect that changes the velocity of a mass-moving object, causing it to accelerate from rest, for example. It is a vector quantity since it can be a push or perhaps a pull and always has magnitude and direction. It is denoted by the letter F and is measured in newtons (N), the SI unit of force (formerly P).
The net force exerted on an object approximately equal to the rate where its momentum varies over time, according to the original formulation of Newton's second law.
The force by the train weight Fw= 150,000N
The force creates by the friction Ff=25,000N
total force =Fw + Ff
= 150,000N+25,000N
= 25,000N
Therefore, 25,000N is the total force.
To know more about force, here:
https://brainly.com/question/13014979
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A sample of oxygen is collected in a 175 mL container over water at 15°C, and the barometer reads 752.0 torr.
What volume would the dry gas occupy at 770.0 torr and 15°C? (Water vapor pressure at 15°C is 12.8 torr.)
The volume of dry gas = 168 L
Further explanationGiven
175 ml container at 15°C
P total = 752 torr
water vapour = 12.8 torr
Required
The volume of dry gas
Solution
Dalton's law of partial pressure :
P tot = P₁ + P₂ + P₃ ....
P total = P O2 + P water
P O2 = 752 - 12.8
P O2 = 739.2 torr
Boyle's Law
At a fixed temperature, the gas volume is inversely proportional to the pressure applied
P₁V₁ = P₂V₂
739.2 175 = 770 .V₂
V₂ = 168 L
Does the following compound contain a polyatomic ion? LiC2H3O2
Yes
No
Answer:
yes
Explanation:
the polyatomic ion is acetate, C2H3O2
What is the atomic mass of this atom?
Answer:
3
Explanation:
The atomic mass is equal to the number of protons in an atom (and electrons if the atom is neutral).
A water molecule is held together by ___ covalent bonds,
meaning there are a total of __shared electrons in the
molecule.
2 covalent bonds
2 pairs or 4 electrons
Which are not combination reactions?
Check all that apply.
A. 2H2O + 2H2 + O2
B. H2 + Cl2 → 2HCI
C. Fe + MgO + Mg + FeO
D. 2Na + Cl2 → 2NaCl
Answer:
A and c
Explanation:
In A the product is added to the reactant, so the real reaction is (2H2O = 2H2+O2).
In B hydrogen and clorine are combined to give hydrochloric acid and 2 is used to balance the reaction in the product, so it's a combination reaction .
In C the case is similar to A , so the real reaction is (Fe+MgO = Mg + FeO ) this is displacement reaction where a more reactive element takes place of a less reactive element .
In D sodium reacting with Chlorine to give sodium chloride ,so we conclude that it's a combination reaction .
True/False: Atoms of the same elements have different properties
Answer: True
Explanation:
Calculate the vapor pressure (in torr) of a 35°C solution of ethanol and propanol where the mole fraction of propanol is .75.
Assume ideal behavior.
P°ethanol = 100 torr
P°propanol = 36 torr
Answer:
i wish i know
Explanation:
Write the complementary RNA strand for the following DNA strand. TAC ACC TTG ACG
Answer:
ATG TGG AAC TGC
Explanation:
ATG TGG AAC TGC
How many moles are in 6.777 x 1023 atoms of CO2. Watch your significant figures. Question 2 options: 1 atoms CO2 1.125 moles CO2 1.13 moles 1.13 atoms CO2
Answer:
1.13moles
Explanation:
Given parameters:
Number of atoms = 6.777 x 10²³ atoms
Unknown:
Number of moles = ?
Solution:
A mole of a substance contains the avogadro's number of particles
6.02 x 10²³ particles = 1 mole
6.777 x 10²³ atoms will contain [tex]\frac{ 6.777 x 10^{23} }{6.02 x 10^{23} }[/tex] = 1.13moles
please help me with this question/
Answer:
4 of each protons and electrons
Explanation:
since the atomic number is 4 it would contain both the same number of protons and electrons
Please answer this question please brianlest
Precipitation falls in these two forms: Solid / Liquid / Gas I’ll give you 77 and read the pdf
Answer:
It falls in Liquid and Solid.
Explanation:
If she traveled 10 m in 5 seconds, what was her average speed?
what is the change in freezing point of a 1.75 molal solution of nacl in water? the kf for water is 1.86 degrees c/m.
Answer:
-6.51
Explanation:
Multiply 1.86 x 2 x 1.74 and then you get your answer.
Answer:
As the molality increases by 1 m, there is a corresponding decrease of 1.86°C in the solution’s freezing point.
Explanation:
Anser on EDge
how many atoms are in each compound ?
2NaCl
H5NO
5NH4C
4Bl
Answer:
i didint understand your question
4 Na + O2 → 2 Na2O
6.79 moles of O2 will react to form how many moles of Na2O?
Answer:
13.94moles of Na₂O
Explanation:
The balanced reaction expression is given as:
4Na + O₂ → 2Na₂O
Given parameters:
Number of moles of O₂ = 6.97moles
Unknown:
Number of moles of Na₂O
Solution:
To solve this problem;
1 mole of O₂ will produce 2 moles of Na₂O ;
6.97 moles of O₂ will produce 6.97 x 2 = 13.94moles of Na₂O
which phrase best defines the term energy
Answer:
theres no options?
Explanation:
The sum of the atomic masses for any compound is the compound’s:
Empirical mass
Compound mass
Atomic mass
Molar mass
Balance the chemical equation. Based on the equation, how many grams of bromine are produced by the complete reaction of 11 grams of potassium bromide?
Answer:
Explanation:
The balanced chemical equation is Cl2 + 2KBr → 2KCl + Br2. The amount of bromine is calculated as follows:
11.0 g KBr (1mol KBr/119.002g KBr * 1mol Br2/2mol KBr * 159.808g Br2/1mol Br2= 7.39 g Br2.)
hello
look at pic and answer
Answer:
Situation 7, also thats funny you were playing nurses office. I like that song. Hope this helped!
what does 'potable water' mean?
Answer:
Potable water, also known as drinking water, comes from surface and ground sources and is treated to levels that that meet state and federal standards for consumption.
Balance the equation
AgBr +
GaPO4 →
Ag3PO4 +
GaBi3
Answer:
3AgBr + GaPO4 ----> Ag3PO4 + GaBr3Explanation:
Which of the following best describes what happens when hydrogen and oxygen to form water?
Atoms are changing place with other atoms
Hydrogen and oxygen are undergoing change of states.
Hydrogen and oxygen are stable condition
Atoms are combining to form molecules
Atoms are combining to form molecules
An apple, potato, and onion all taste the same if you eat them with your nose plugged
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Hey, love!
You only get that little quote if your streak gets higher so, congrats on that!
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True or False- Waves are caused by the water being pushed by the wind, which transfers energy, that can cause erosion to the shorelines .
Answer:
false
Explanation:
Waves are created because othe the lunar pull with out the moon we wouldnt have waves
7. Although carbon's three isotopes are carbon-12, carbon-13, and carbon-14, its
average atomic mass is 12.01 because
A. carbon-12 is the heaviest isotope.
B. carbon-12 is most useful to humans.
C. carbon-12 is the most common isotope.
Answer:
B
Explanation:
carbon 12 is most useful to humans