Answer:
Resources
Explanation:
Answer:
Explanation:
M
what percent of a sample of a radioactive element whose half life=5.0 years will decay after 25 years?
Answer:
Calculate the rate of decay constant for U-238 if its half-life is 4.468 × 109 years. Answer: If the problem is referring to the half-life, then the ratio of = 0.5 because half of the original sample has already undergone decay.
Explanation:
please someone help me its due today thanks :D
Answer:
D
Explanation:
All of the above are great examples!
"Endothermic reactions are those which absorb heat during the reaction."
Match the term with the definition.
Condensation
Evaporation
Sublimation
Freezing
A) A phase change from a gas to a liquid
B) A phase change from a solid to a gas
C) A phase change from a liquid to a gas
D) A phase change from a liquid to a solid
[Please Hellp!]
Which molecule has the strongest forces of attraction between molecules?
Dipole-dipole interactions are the strongest intermolecular pressure of attraction.
Answer: Dipole-dipole interactions are the strongest intermolecular force of attraction.
Explanation:
How many Joules of heat are needed to melt 3.0 g of ice?
Answer:A substance must absorb heat energy so that it can melt or boil. The temperature of the substance does not change during melting, boiling or freezing - even though energy is still being transferred
Explanation:imm not sure
HELPP!!! ASAP!!!! BRAINLIEST!!!
Complete the following sentences. Energy is required to _______ bonds in a molecule and released when bonds are _______.
Answer:
Energy is required to break bonds in a molecule and released when bonds are made.
Explanation:
Energy is added to break bonds and released when making bonds.
A 75.0 gram sample of water at 25.0 degrees Celsius is mixed with a 100. Gram sample of water at 60.0 degrees Celsius. What is the final temperature of the water?
Answer:
The final temperature of the water = 45°C
Explanation:
Heat lost = heat gained
Heat lost by water at 60°C = m₁CΔT₁
Heat gained by water at 25°C = m₂CΔT₂
where m₁ is mass of water at 60°C = 100.0 g; m₂ is mass of water at 25°C = 75.0 g
C, specific heat capacity of water = 4.18 J/g°C
ΔT₁ = (60 - T); ΔT₂ = (T - 25); T = final temperature of the water
m₁CΔT₁ = m₂CΔT₂
100 * C * (60 - T) = 75 * C * (T - 25)
-100T + 6000 = 75T - 1875
-(100T + 75T) = -(6000 + 1875)
175T = 7875
T = 45°C
Therefore, final temperature of the water = 45°C
which element has a higher atomic number of aluminum or oxygen
Answer:
aluminum
Explanation:
oxygen's atomic number is 8.
aluminum's atomic number is 13.
When determining an element’s chemical properties, the most important subatomic particle to look at is
Answer:
Electrons
Explanation:
When determining the chemical properties of elements, the most important subatomic particle to consider is the electrons.
Electrons are negatively charged particles that orbits an atom. They occupy the extranuclear space of an atom.
These electrons determines the chemical properties of each atom. Most especially, the valence ones. All elements wants to resemble the noble gases, so they alter their number of electrons in order to attain this stable state.
Which compound is
ionic?
Answer:
chemistry
Explanation:
What is one danger associated with the use of hydrogen gas
Answer:
Topping the list of concerns is hydrogen burns. In the presence of an oxidizer -- oxygen is a good one -- hydrogen can catch fire, sometimes explosively, and it burns more easily than gasoline does.
Answer:
hydrogen burns
hope it helps
The breaking and forming of bonds between atoms in substances results in changes in the _______ contained in the substances.
Answer:
Electrons
Explanation:
The breaking and forming of bonds between atoms in substances results in changes in the number of electrons in the substance.
Atoms combined in order to share, gain or lose electrons for it to be stable. The noble gases have a set up configuration which makes them stable. All atom tend to mimic the noble gases.Identify the number of electrons
Atomic mass: 24
Atomic number: 12
-2 charge
Answer:
24 is the answer of this question
Which atom in the following sets has the larger atomic radius?
a. Rn, Ne, Ar, Kr
b. Hg, Cs, Po, W
c. Mg, P, Al, Ar
Answer:
A.Rn,Ne,Ar,Kr.......
Is copper sulphate malleable?
Answer:
Yes, Copper (Cu) in its pure form is a reddish-brown metallic element with high ductility and malleability that is an excellent conductor of heat and electricity: atomic weight 63.54; atomic number 29; density 8.94 g/cm3; melting point 1083°C; and boiling point 2595°C.
Answer:
no ,its not malleable
Explanation:
copper II sulphate is a blue compound , which is brittle solid , crystalline .
copper metal is malleable and ductile
Ian uses litmus paper to determine whether five unknown solutions are acids or bases. The litmus paper turns red when the pH is 4.5 or below and blue when the pH is 8.2 or above. Ian records the results in the data table.
Ian accidentally spills a beaker of an unknown solution. It splashes onto the strip he used to test Solution 1, and the strip turns from red to blue. Based on this observation, which conclusion could Ian make about the solution that he spilled?
Answer: b
explanation: i had the question on a test and got it right.
The diagram below shows the distance traveled by two light waves in 1 second.
Based on the diagram, which of these conclusions is correct?
The frequency of Wave 1 is double the frequency of Wave 2.
The frequency of Wave 2 is double the frequency of Wave 1.
The wavelength of Wave 1 is four times the wavelength of Wave 2.
The wavelength of Wave 2 is four times the wavelength of Wave 1.
Please help
Answer:
The frequency of Wave 2 is double the frequency of Wave 1.
Explanation:
Waves with higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths.
Use the equation below to solve the problem that follows.
2H2 (g) + O2 (g) → 2H2O (g)
When David reacts 13.8 grams of hydrogen gas with excess oxygen, 87.0 grams of water are formed. Calculate his percent yield of water.
Answer: 142.8%
Explanation:
13.8g H2 * (1 mol H2 / 2 g H2) * (2 mol H2O/ 2 mol H2) * (18 g H2O/1 mol H2O) = 124.2 g H2O
we just calculated our theoretical amount that should be formed and we are given the actual
percent yield: actual/theo * 100% = 124.2/87 * 100% = 142.8%
8)How many grams are in 0.02 moles of beryllium iodide, BeI2?
9)How many moles are in 68 grams of copper (II) hydroxide, Cu(OH)2?
10)How many grams are in 3.3 moles of potassium sulfide, K2S?
11) How many grams are in 2.3 x 10-4 moles of calcium phosphate, Ca3(PO3)2?
Answer:
0.03:---$7--$-$7$--$-$-$$-$+-$$7-$$-$7-$8$+$-$
PLEASE HELP!!!!! NEED HELP ASAP!!!!!
Write the chemical formula for the ionic compounds below
EXAMPLE- Calcium Phosphide= Ca3P2
Magnesium chloride=
Aluminum Fluoride=
Lithium Bromide=
Potassium Sulfide=
Answer:
down below
Explanation:
MgCl2
AlF3
LiBr
K2S
how can air produce a pressure
IN OWN WORDS NOT FROM GOOGLE
Answer:
Gas pressure is caused when gas particles hit the wall of their contains. the more often the particles hit the walls, and the faster they are moving when they do this , the higher the pressure .
Explanation:
Predict the products for the following chemical reaction: H2 + O2 →
a. H30
b. H20
c. H2OH
d. OH + OH
O a
How many moles of
C
O
2
COX
2
will be produced from
97.0
g
97.0 g97, point, 0, start text, space, g, end text of
C
3
H
8
CX
3
HX
8
, assuming
O
2
OX
2
is available in excess?
Answer:
Im highy
Explanation:
Explain why both a power source (like a battery) and a complete circuit are necessary for an electromagnet to function.
this is science homework by the way, please help me with it:)
Answer:
Electromagnets are only functional when electricity is passing through them. In other words, they only create a magnetic field when there is an electric current flowing.
A power source like a battery is therefore necessary to supply the electric current necessary for the magnet to work however, it will not work unless the circuit is closed as electricity cannot not flow in an open circuit because current needs to be able to flow from one end of a power source to the other end.
Explanation:
ha hot dog hamburger hamburger ng baboy hahaha bomba girl home baboy
What would be a reasonable pH level of the dish soap in your kitchen?
Answer:around 7
If your dish soap is labeled mild, gentle, or great for hands, chances are its pH level is somewhere right around 7. This mildness makes dish soap perfect for day to day cleaning. Most surfaces won't be damaged by dish soap, and there are a lot of places it can be used besides in the kitchen sink
Explanation: I have had this question before
Answer:
7
Explanation:
Considering that you use dish soap on a daily occurence... it is best for it to be versatile. By making it 7... it is very neutral.
This means it's not too acidic for some situations... nor is it too basic in other situations.
The theory of plate tectonics was, at first, rejected by most scientists. Now most geologists accept that tectonic plates exist and that these tectonic plates can and do move. What is responsible for the change in how scientists think about plate tectonics?
Answer:
The validation of seafloor spreading in the 1950s and 60s
Explanation:
The theory of seafloor spreading was supported by numerous evidence including thermal probes that showed that heat flow over the mid-ocean ridges measured up to four times those measured in general bottom sediments, which are taken as due to the presence of molten Earth material close to the ridge crest
The ridge crest also show signs unusually seismic wave velocities that are considered to be due to microfracturing and thermal expansion from upwelling magma
Ernest Rutherford built on the work of previous scientists and improved the accuracy of the atomic model. What part of the atom is Rutherford
credited for discovering?
A.) The protons
B.) The electrons
C.) The nucleus
D.)The electron cloud
Classify each organic compound based on the functional group it contains.
ether
carboxylic acid
ester
alcohol
Molecular Structure
Type of Compound
I-O-I
Η Ο
1 10
C-C-0-H
1
H
H
-I
H
II
H
1
H-C
1
H
H
1
-C
1
H
1
H
1
H
1
H
H
I
H-C
1
H
H H
I
C-0-C-H
1
1
H H
1
H-CC-O-H
1
H H
Answer:
H2C2O1
Explanation:
Answer:
Carboxylic Acid
Ester
Ether
Alcohol
Explanation:
Which of the following are soluble in water: salt, gravel, or pepper
what are chiral carbon
Answer:
A chiral carbon is a carbon bonded to four different groups ( four groups as carbon forms four bonds). The molecules formed are non superimposible on its mirror image.