Answer:
A-cycles of the moon
Explanation:
The people of Ancient Greece, Rome and China counted their year based on a 12 moon cycle ( that is, about 354 days). A 13th cycle of the moon is included so that the lunar year remains in step with the seasons of the year.
Today, the Gregorian calendar is mostly used around the world. This calendar was
actually adapted from an earlier lunar version. Ancient civilizations used the phases of the moon to help identify the seasons.
The major difference between the lunar calendar and the solar calendar is the kind of celestial body that is used to determine time.
The mass of the product of a reaction will always equal what
I NEED ASAP PLEASE!!
Answer: freezing and evaporation for sure
Explanation:
9. An atom's electron configuration is shown here. How many electrons are in
that atom?
1s22s22p63s4
8
14
4
22
Answer:
14 electrons are in that atom
define the law conservation of mass
Answer:
Explanation:
The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as the system's mass cannot change, so the quantity can neither be added nor be removed.
hope it helps
__
19. SC.912.L.18.12
The picture below shows a group of water skate bugs "walking on the surface of a pond. When an
insect lands or falls into the water, the water molecules vibrate. The water skater uses the resulting
vibrations to find its prey. What property of water enables this bug to stay on the surface of the pond
and not sink?
a. Water's high specific heat enhances the vibrations causing the bugs to float.
b. An optimum pH of the pond water, keeps the water calm so that the bugs don't
sink.
C. The hydrogen atoms, in the water, bond to the bugs' legs keeping the bugs on the
surface.
d. Hydrogen bonds provide cohesion of the water molecules enabling the bugs to stay
afloat.
Answer: Hydrogen bonds provide cohesion of the water molecules enabling the bugs to stay
afloat.
Explanation: Hope it helps :)
Hydrogen bonds provide cohesion of the water molecules enabling the bugs to stay.
Water:
The Earth is made up of 75% water. river, lakes, sea are some of the sources of water. Hydrogen bonds between the water molecules help to bind the molecules together.
Water molecules has cohesive property, due to this cohesive property all the hydrogen molecules bugs can easily afloat on surface of water.
There are the two types of properties such as cohesion and adhesion. Cohesion allows insects to walk.
Option C is the correct answer.
Therefore, Hydrogen bonds provide cohesion of the water molecules enabling the bugs to stay.
To learn more about hydrogen bond, refer to the link:
https://brainly.com/question/15099999
#SPJ2
Make a list of characteristics that all waves have in common
Answer:
sound waves, light waves, radio waves, microwaves and others
Explanation:
these waves have the same fundamental properties of reflection ,refraction, diffraction and interference, and all waves have a wavelength, frequency, speed and amplitude
Why were Democritus's ideas not science?
Answer:
Im not sure because you might have spelled a word wrong.But i believe because of their certain treaditions,belifs,and ways.
Explanation:
Which part of the atom is responsible for chemical bonding?
Answer:
valence electrons
Explanation:
The electrons of an atom, in particular valence electrons, are involved in chemical bonding
how are speed and velocity alike?
Answer:
The answer will be listed below.
Explanation:
Speed and velocity both represent a way to measure the change in position of an object relative to time. If the motion is in a straight lne, then the speed and velocity would be the same. When measuring speed and velocity, they are used in m/s.
5. Explain the difference between a molecular
element and a molecular compound.
Answer:
is that in a molecule of an element, all the atoms are the same. For example, in a molecule of water (a compound), there is one oxygen atom and two hydrogen atoms. But in a molecule of oxygen (an element), both of the atoms are oxygen.
Explanation:
Answer:
The only difference between a molecule of a compound and a molecule of an element is that in a molecule of an element all the atoms are the same.
Explanation: A molecule of an element all the atoms are the same.
Red lights on a traffic light have a frequency of 4.3 X 1015 Hz. What is the red light’s wavelength in meters?
The wavelength of light is found to be 6.98 × 10^-8 m.
We know that light is an electromagnetic wave, the speed of an electromagnetic wave is commonly referred to as the speed of light which has a numerical value of 3 × 10^8 m/s.
Now;
c = λf
c = speed of light
λ = wavelength of light
f = frequency of light
But;
λ = c/f
λ = 3 × 10^8 m/s/ 4.3 X 10^15 Hz
λ = 6.98 × 10^-8 m
Learn more light waves: https://brainly.com/question/14588679
Classify the following materials rock or mineral
Answer:
Common minerals include quartz, feldspar, mica, amphibole, olivine, and calcite. A rock is an aggregate of one or more minerals, or a body of undifferentiated mineral matter. Common rocks include granite, basalt, limestone, and sandstone.
Help pls also i will give brainliest!
A company purchased a large forest and cut the trees for lumber. Sunlight which had not reached the forest floor before was now very bright on the bare ground. Holly ferns began to grow rapidly because of increased access to light and moisture.
Which population of organisms would be in direct competition with the Holly ferns for the same resources?
A) Squirrels
B) Hawks
C) Spotted owls
D) Wildflowers
Answer:
It's D) Wildflowers
Hope it helps!!!
Give evidence to support or dispute: “In nature, the chance of finding one isotope of an element is the same for all elements.”
Answer:
False, isotopes have different occurrence percentages, so the changes are different.
Explanation:
Hello,
In this case, since it is false that the isotopes of all the elements can be found with the same chance (occurrence) we can consider the following facts:
1. Carbon atom has two major occurring isotopes: C-12 (98.93%) and C-13 (1.07%).
2. Bromine atom has two major occurring isotopes: Br-79 (50.69%) and Br-81 (49.31%).
3. Calcium has four major occurring isotopes: Ca-40 (96.941%), Ca-42 (0.647%), Ca-43 (0.135%) and Ca-44 (2.086%).
Which show us that the chances of finding any isotope differ among elements.
Regards.
The statement presented in the question above is false, as the percentage of occurrence of an isotope cannot be defined and adopted for all elements, as this varies.
We can arrive at this answer because:
Isotopes are chemical elements that have the same amount of protons.However, these elements have different mass numbers and neutrons from each other.Although there is a percentage of occurrence of isotopes in nature, this percentage varies among elements.Mainly because these elements compose different substances and some may have low occurrence percentages and others high percentages.An example of this can be seen in Calcium (Ca) isotopes, where the Ca-40 isotope has an occurrence percentage equal to 96.9%, while the Ca-42 isotope has an occurrence percentage equal to 0.64%.
More information:
https://brainly.com/question/14667931?referrer=searchResults
Name two characteristics that a thing must have to be called matter.
Answer:
mass is one
Explanation:
Answer:
mass and volume are the correct answers
50.0 g of NaNO3 are dissolved into enough water to make 250 mL of solution. What is the molarity of this solution?
Answer:
2.35 M
Explanation:
Molarity is mol/L of solution. We have to convert the g to mol and the mL to L. G to mol uses the molar mass of the compound. The molar mass of NaNO₃ is 85.00g/mol.
[tex]50.0gNaNO3*\frac{1molNaNO3}{85.00gNaNO3} = 0.588molNaNO3[/tex]
Then you have to convert mL to L.
[tex]250mL*\frac{1L}{1000mL} = 0.250L[/tex]
Now divide the mol by the L.
[tex]\frac{0.588mol NaNO3}{0.250L} = 2.352 M[/tex]
Round to the smallest number of significant figures = 2.35M
Explain why a melted ionic compound is a good conductor of electric current by a solid ionic compound is a poor conductor of electric current?
Answer:
Melted ionic compounds have freely moving ions while solid ionic compounds do not.
Explanation:
A melted ionic compound has freely moving ions where electrons can be transfered because the elements of the ionic compounds have broken there bonds and have dissociated into their ions. Compared to a solid ionic compound where it's still in the crystal lattice and the elements will stick in place and the ions will not move because it's in a solid state and they haven't dissocated into their ions.
Write the products of these double-replacement reaction. Then balance each equation. Ba(NO3)2 (aq) + H3PO4 (aq) ---> Barium phosphate is a precipitate)
Answer:
Explanation:
Step 1: RxN
Ba(NO₃)₂ (aq) + H₃PO₄ (aq) → Ba₃(PO₄)₂ (s) + HNO₃ (aq)
Step 2: Balance RxN
We need 3 Ba's on both sides.
We need 2 PO₄'s on both sides.
3Ba(NO₃)₂ (aq) + 2H₃PO₄ (aq) → Ba₃(PO₄)₂ (s) + 6HNO₃ (aq)
Why is it more difficult to cause photons to be emitted from neon
Answer:
Neon is a noble gas
Explanation:
It is important to note that the excitation energy of even the lowest excited states of noble gases is greater than the ionization energy of many atoms of other elements.
This is because, the electrons in a noble gas are contained in a filled shell with greater stability than the the atoms of other elements.
Hence, it becomes difficult to excite the neon atom to a higher energy level.
Recall that photons are emitted when atoms of elements return to ground state after being excited to higher energy level.
Since it is difficult to excite neon, it is also difficult to cause photons to be emitted from neon.
Which type of force caused the weight to drop (11) after the rope was cut?
Friction Force
Normal Force
Applied Force
Electrical Force
Gravitational Force
Magnetic Force
Answer:
gravitational force.
More people in Australia have skin that is easily damaged by sunlight?
What what is the density. Correct units please.
What is the identity of the metal?
Mass of metal: 12.3 g
Initial volume: 20.5 mL
Final volume: 21.9 mL
What is the IUPAC name for CH3-CH2-CH(OH)CH3?
Answer:
2 butanol or sec butanol
Paul and Karen were studying physical and chemical properties of matter. They determined that the mass of a sample was 50 grams. Which sentence BEST states
how mass describes matter?
A. The mass of a substance is a way to measure the amount of matter it contains.
O B. Mass is a way to measure the force of gravity on a substance.
o
C. Mass is a chemical property of a substance.
D. The mass of a substance may change, based on its location.
Answer:
A
Explanation:
Mass is a measure of the amount of matter in an object.
The mass of a substance measures the amount of matter it contains. Therefore, option A is correct.
What is mass?Mass can be explained as an intrinsic property of an object. Mass can be described the amount of matter in a body. Different atoms or different particles with the same amount of matter possess nonetheless different masses.
Mass can be experimentally determined by the body's inertia, meaning the resistance to an acceleration of the body when a net force is applied. The mass evaluates the strength of the gravitational attraction to the bodies.
The S.I. base unit of measurement of mass can be represented by the kilogram (kg) but it is not the same as that of weight. Mass can be defined as generally measuring the weight utilizing a spring scale, rather than a balance scale and comparing it to already known masses.
A body on the Moon will weigh less than on Earth due to the lower gravity on the moon but still have equal mass. Paul and Karen determined that the mass of a sample was 50 g which is the amount of matter it contains.
Learn more about mass, here:
brainly.com/question/13040516
#SPJ2
Which of the following is the sun responsible for?
A-Earth’s magnetic field
B-Earth’s temperature
C-Earth’s atmosphere
D-Earth’s rotation
Answer:
Im pretty sure it is B. Earths temperature
Explanation:
what special quality does the asthenosphere have that allows the crust to float on it and be moved around ?
Answer:
The tectonic plates do not slowly drift over time because they are floating on a layer of liquid rock. They drift because they are sitting on a layer of solid rock (the upper mantle or "asthenosphere") that is weak and ductile enough that it can flow very slowly under heat convection, somewhat like a liquid.
Explanation:
Some oxides are given below. (i)Na2O (ii)NO2 (iii) CO2 (iv) MgO a) Which are the basic oxides among these? b) What is the name of the aqueous solution of CO2 ?
Basic oxides ⇒ metal(usually alkali/alkaline earth) +O₂
L + O₂ ⇒ L₂O
L + O₂ ⇒ LO
Dissolve in water becomes = basic solution
L₂O+H₂O⇒ 2LOH
LO + H₂O⇒ L(OH)₂
So the basic oxides : Na₂O and MgO
Na₂O + H₂O⇒NaOH
MgO +H₂O⇒Mg(OH)₂
The aqueous solution of CO₂(dissolve in water)
CO₂ + +H₂O⇒ H₂CO₃(carbonic acid)
Why do you think experimenters work in labs instead of the natural world?
Answer:
I think experiments work in a lab better than the natural world because you got all the equipment that you need in the lab
what is the percentage of hydrogen in 300 g of sucrose?
Answer:
hi
Explanation:
Answer: 6.50%
Explanation:
It is this answer simply because they're the same substance.
during energy transformations energy is never
Answer:
created or destroyed
Explanation: