Answer:
4 weeks
Explanation:
It takes 4 weeks for the cyclle to be happening again
Only the ______ has successfully landed men on the moon.
Answer: The United States
The United States is the only country to have successfully conducted crewed missions to the Moon, with the last departing the lunar surface in December 1972.
Explanation:
Answer
Only the United States has successfully landed men on the moon.
Explanation:
The United States is the only country to have successfully conducted crewed missions to the Moon, with the last departing the lunar surface in December 1972.
1:Krypton gain or lose electrons
2:Strontium gain or lose electrons
3:Xenon gain or lose electrons
Answer:
Krypton gain
strontium lose
xenon neither gain or lose
Need a little help with science please
Answer:
I'm pretty sure its liver and pancreas
Explanation:
the pancreas delivers the digestive juice to the small intestine through small tubes, your liver makes the digestive juices called the bile that helps digest fats and some vitamins
Answer:
the answer is liver and pancreas
A sample of pure radioactive isotope is left to decay. After 40.0 days, the 1 point
sample is placed in a mass spectrometer, and it is determined that only
25% of the original isotope remains. How long is the half-life?
Answer:
6 months and 1 day
Explanation:
Is luster a chemical or physical change? (Worth 50 POINTS!)
Answer:
It is a Physical change, have a great day :)
Explanation:
A chemical change is a permanent change. A Physical change affects only physical properties i.e. shape, size, etc. ... Some examples of physical change are freezing of water, melting of wax, boiling of water, etc. A few examples of chemical change are digestion of food, burning of coal, rusting, etc.
SOMEONE HELP PLS ILL GIVE BRAINLIEST AND 19 PT
Sample left = 6.25 g
The percentage = 6.25%
Further explanationGiven
t1/2 = half-life = 3.8 days
t = decay time = 15.2 days
No = initial sample = 100 g
Required
Nt = final sample left
The percentage
Solution
General formulas used in decay:
[tex]\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}[/tex]
Input the value :
[tex]\tt N_t=100.\dfrac{1}{2}^{15.2/3.8}\\\\N_t=100.\dfrac{1}{2}^4\\\\N_t=6.25~g[/tex]
The percentage : Nt/No
6.25 : 100 = 6.25%
A potted plant is placed under a grow lamp, which provides 4,200 J of energy to the plant and the soil over the course of an hour. The specific heat capacity of the soil is about 0.84 J/g° C and there are about 2,400 g of soil. How much does the temperature of the soil increase?
Answer:
Temperature increase = ΔT = 2.08 °C
Explanation:
Given data:
Energy absorbed by plant = 4200 J
Specific heat capacity of soil = 0.84 J/g°C
Mass of soil = 2400 g
How much temperature increase = ?
Solution:
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
by putting values,
4200 J = 2400 g ×0.84 J/g°C × ΔT
4200 J = 2016 J/°C × ΔT
ΔT = 4200 J / 2016 J/°C
ΔT = 2.08 °C
Mg(s) + HCl(aq) −→ MgCl2(aq) + H2(g).
What mass of HCl is consumed by the reaction of 2.28 mol of magnesium?
Answer in units of g
166 g HCl
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
BracketsParenthesisExponentsMultiplicationDivisionAdditionSubtractionLeft to RightChemistry
Stoichiometry
Reading a Periodic TableBalancing EquationsUsing Dimensional AnalysisExplanation:Step 1: Define
[RxN - Unbalanced] Mg (s) + HCl (aq) → MgCl₂ (aq) + H₂ (g)
[RxN - Balanced] Mg (s) + 2HCl (aq) → MgCl₂ (aq) + H₂ (g)
[Given] 2.28 mol Mg (s)
Step 2: Identify Conversions
[RxN] 1 mol Mg = 2 mol HCl
Molar Mass of H - 1.01 g/mol
Molar Mass of Cl - 35.45 g/mol
Molar Mass of HCl - 1.01 + 35.45 = 36.46 g/mol
Step 3: Stoichiometry
Set up: [tex]\displaystyle 2.28 \ mol \ Mg(\frac{2 \ mol \ HCl}{1 \ mol \ Mg})(\frac{36.46 \ g \ HCl}{1 \ mol \ HCl})[/tex]Multiply: [tex]\displaystyle 166.258 \ g \ HCl[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
166.258 g HCl ≈ 166 g HCl
In the compound Al2O3, aluminum has an oxidation number of 3, while oxygen's oxidation number is ________.
Answer:
The oxidation number of Oxygen is -2.
Answer:
-2
Explanation:
I just had that question!
Write this in a word and skeleton equation:
Solid silver chloride and an aqueous solution of nitric acid are produced when a solution of silver nitrate is reacted with a solution of hydrochloric acid.
Answer:
Write this in a word and skeleton equation:
Solid silver chloride and an aqueous solution of nitric acid are produced when a solution of silver nitrate is reacted with a solution of hydrochloric acid.
Explanation:
List 3 different sugars found in this product. *
3 points
INGREDIENTS / INGRÉDIENTS :
CORN MEAL, SUGAR, CORN BRAN, CORN SYRUP,
MALTODEXTRIN, FANCY MOLASSES, SALT, WHOLE OAT FLOUR.
BAKING SODA, NATURAL FLAVOUR, COLOUR (CAROTENE),
VITAMINS AND MINERALS: IRON, ZINC OXIDE, NIACINAMIDE,
d-CALCIUM PANTOTHENATE, THIAMINE HYDROCHLORIDE,
CHOLECALCIFEROL (VITAMIN D3), PYRIDOXINE
HYDROCHLORIDE, FOLIC ACID.
CONTAINS OAT INGREDIENTS. MAY CONTAIN SOY.
SEMOULE DE MAÏS, SUCRE, SON DE MAÏS, SIROP DE MAÏS,
MALTODEXTRINE, MÉLASSE QUALITÉ FANTAISIE, SEL, FARINE
D'AVOINE ENTIÈRE, BICARBONATE DE SODIUM, ARÔME
NATUREL, COLORANT (CAROTENE),
VITAMINES ET MINÉRAUX : FER, OXYDE DE ZINC,
NIACINAMIDE, d-PANTOTHÉNATE DE CALCIUM,
CHLORHYDRATE DE THIAMINE, CHOLÉCALCIFÉROL (VITAMINE
D3), CHLORHYDRATE DE PYRIDOXINE, ACIDE FOLIQUE,
CONTIENT DES INGRÉDIENTS DE L'AVOINE. PEUT CONTENIR DU SOYA.
Answer:
Sugar (Sucrose), Corn Syrup (Glucose), Molasses (C6H12NNaO3S)
Explanation:
Each of these is a sweetener.
Need help with this question please I’m really really going to appreciate it
Answer:
Alpha
Explanation:
^4 _2 He = alpha
^0 _-1 b = beta
^0 _0 y = gamma
The substance that is produced from a chemical reaction
•reactants
•chemical reaction
•atom
•product
•molecule
Answer - The substance that is produced from a chemical reaction....
REACTANTS
A sample of He has volume of 4.40 L at 555 torr and 33.0 C. Find the new pressure if the volume decreases to 3.50 L and the temperature increases to 44.0 C.
723 torr
504 torr
800. torr
612 torr
Answer:
723 torr
Explanation:
Using the formula;
P1V1/T1 = P2V2/T2
Where;
P1 = initial pressure (torr)
V1 = initial volume (Litres)
T1 = initial temperature (°C)
P2 = final pressure (torr)
V2 = final volume (L)
T2 = final temperature (°C)
Based on the information provided in this question, V1 = 4.40L, P1 = 555 torr, T1 = 33.0 °C + 273 = 306K, V2 = 3.50 L, P2 = ?, T2 = 44.0 °C + 273 = 317K.
Using the formula above:
555 × 4.4/306 = P2 × 3.5/317
2442/306 = 3.5P2/317
Cross multiply;
2442 × 317 = 306 × 3.5P2
774114 = 1071 P2
P2 = 774114 ÷ 1071
P2 = 722.79
P2 = 723 Torr
What percent of I-125 has decayed if there are 37.5g of the original sample left?
Answer:
[(x-37.5)/x]*100%
62.5% (assuming the original sample weighs 100.0g)
Explanation:
Let's say that the original sample is x
Mass of I-125 which has decayed: x-37.5
Percentage of decayed mass: [(x-37.5)/x]*100%
Please recheck, for this may not be the correct answer
What is the correct number of digits to express a measurement
Answer:
Examples of measured numbers: The diameter of a coin, such as 10.2 mm. The weight of an object, such as 8.887 grams. The length of a pen, such as 12 cm.
Explanation:
Answer:
It completely depends on what you are measuring, what instrument you are using, and the uncertainty associated with your measurement.
Explanation:
When expressing a measurement, there is always going to be a part that you know, and a part that you guess. They both make up known numbers collectively called significant figures (commonly shortened to "sig figs"). For instance, imagine you are measuring the length of a pencil. Let's say it is a typical ruler with divisions of 0.1 cm (picture for reference). You measure the pencil, and to your eyes it looks like it is about 9 cm and 5 small tick marks (so, 0.5 cm), so we'll call that 9.5 cm. Now, this is a known value, so you are certain that it is a least 9.5 cm. However, it may be true that there is one more decimal place that can be known. The general rule is that you want to add one more uncertain digit to the rightmost side of the number, and how many digits depends on the divisions of the instrument. Our ruler has divisions of 0.1 cm (the small tick marks), and so we will go one more place out, and add another digit. Now, let's say our eyes are pretty good, so let's say it's 9.5 cm, and then add that one uncertain digit, a 0 to the smallest division of 0.1, so, 0.10. The final measurement we record is 9.50 cm. Now, it may seem like we are simply guessing or even being unreasonable in our assessment of how long this pencil is. I can promise you that not knowing the actual measurement of this pencil will not make a spaceship crash because of a specification that was not the "right measurement". For those life-or-death measurements, much more precise measurement machines are used; this is just a pencil. Also, it would be unreasonable to say that it is 9.500000 cm or 9.500001 cm. We do not have that kind of certainty with this ruler, only divisions of 0.1 cm, so we can only estimate out to one more decimal place.
In short, find the smallest division of a ruler or whatever device (like a chemical beaker) you are using, and then add one uncertain digit to the end of that. If it's 0.1 cm, then add one digit to that. (example: 5.6 --> 5.63; 3 because that is what it looks like on the ruler). If it's 1 cm, then add an extra .1, so the measurement is 1.1 cm. And of course, it's not always cm you are using, that was just an example. Best of luck!
16. DNA in a eukaryotic cell is contained in
A) a nucleus
B) a protein molecule
C) an enzyme molecule
D) a chromosome
Answer:
A. Nucleus
Nucleus is the answe
How are clouds formed? Simple answer please!
Answer:
Clouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. For this to happen, the parcel of air must be saturated, i.e. unable to hold all the water it contains in vapor form, so it starts to condense into a liquid or solid form.
Explanation:
MARK ME BRAINLIEST!!!!!!!! THANKS BESTFRIENNNNNDDDDD!!!!!!!!
Answer:
Clouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. For this to happen, the parcel of air must be saturated, i.e. unable to hold all the water it contains in vapor form, so it starts to condense into a liquid or solid form.
Explanation:
I HOPE THIS HELPS*--- *meow*
what is a displacement reactions
A displacement reaction is the one wherein the atom or a set of atoms is displaced by another atom in a molecule. For instance, when iron is added to a copper sulphate solution, it displaces the copper metal.
A + BC → AC + B
The above equation exists when A is more reactive than B.
A and B have to be either:
Halogens where C indicates a cation.
Different metals wherein C indicates an anion.
[tex]\textsf{what is a displacement reactions? }[/tex]
Answer:[tex]\large \underbrace{ \underline{ \sf Displacement \: reaction}}[/tex]
The reaction in which more reactive element replace a less reactive element from its compound is called displacement reaction.
Ex:-
[tex]\bold{\large Zn+HCl \longrightarrow ZnCl_2+H_2}[/tex]
Many human activities result in carbon dioxide emissions.
Our carbon footprint is a measure of how much carbon dioxide we each cause to be produced.
(a) Why should we be concerned about our carbon footprint?
(b) Most power stations in the UK burn coal.
Coal was formed from tree-like plants over millions of years.
Suggest why burning wood instead of coal would help to reduce our carbon footprint.
Answer:
: the average human-driven CO2 emissions per year climbed 1.4%
every household makes about 7 tons worth of Co2
A C02 footprints are produced at such high rates and hurts plants and the environment
B coal is a very inexpensive and efficient way to generate electricity. Since its a large quantity of them which still produces alot co2 unlike wood, burning wood doesn't produce as much but it's much harder to ignite and get to last because it takes coal almost 100 degrees and wood takes about 700 degrees
How can calcium oxide change directly to limewater?
Wants equation and observation
Answer:
Lime(Calcium Oxide) is a white solid with strongly basic properties.Lime reacts readily with water to produce slaked lime,which is the chemical compound calcium hydroxide.....
When carbon dioxide gas is passed through or over limewater,it turns milky due to the formation of calcium carbonate.
1. Calculate the RFM of Fe(NO3)2
Answer:
The Relative Formula Mass of Fe(NO₃)₂ is 179.8524 grams
Explanation:
The Relative Formula Mass is the mass of one mole of a compound expressed in grams, obtained by adding together the Relative Atomic Masses, RAM, of the elements which makes the compound
The Relative Formula Mass of a compound is the same as its Relative Molecular Mass
The relative formula mass of Fe(NO₃)₂ is given as follows;
The relative atomic mass of Fe = 55.845 amu
The relative atomic mass of nitrogen, N = 14.0067 amu
The relative atomic mass of oxygen, O = 15.999 amu
Therefore, we have;
The formula mass of Fe(NO₃)₂ = (55.845 + 2×(14.0067 + 3×15.999)) amu = 179.8524 amu
The Relative Formula Mass of Fe(NO₃)₂ = 179.8524 grams.
What do all volcanos emit?
Answer:
By far the most abundant volcanic gas is water vapor, which is harmless. However, significant amounts of carbon dioxide, sulfur dioxide, hydrogen sulfide and hydrogen halides can also be emitted from volcanoes.
Stephanie the Skydiver has a mass of 48kg, what is the force that she
exerts as she is falling to the ground?
Answer:
470.4N
Explanation:
Given parameters:
Mass of Stephanie = 48kg
Unknown:
Force she exerts while falling to the ground = ?
Solution:
The force she exerts is her weight;
Weight = mass x acceleration due to gravity
Now insert the parameters ands solve ;
Weight = 48 x 9.8 = 470.4N
can someone please help me, i'll give you a 5 star rating and brainliest answer
the bond between which two atoms is most polar
Answer:
bond
Explanation:
It is a polar bond because it is when two atoms bond
Hydrogen bonds are in the family of Van der Waals forces. They are weaker than ionic and covalent bonds but they cause interesting changes with different chemicals.
What is one of the changes that hydrogen bonds are responsible for?
A. Cause DNA has the double helix shape.
B. Causes salts quickly dissolve in water.
C. Cause sugar looks like a crystal.
D. Cause liquid H2O to have a larger volume than frozen (solid) H2O
Answer:
The answer is B. Van der Waals forces are weaker than ionic and covalent bonds.
Explanation:
In general, if we arrange these molecular forces from the strongest to weakest, it would be like this:
Covalent bonds > Ionic bonds > Hydrogen bonds > Dipole-Dipole Interactions > Van der Waals forces
Covalent bonds are known to have the strongest and most stable bonds since they go deep and into the inter-molecular state. A diamond is an example of a compound with this characteristic bond.
Ionic bonds are the next strongest molecular bond following covalent bonds. This is due to the protons and electrons causing an electro-static force which results to the strong bonds. An example would be Sodium Chloride (NaCl), which when separated is Na⁺ and Cl⁻.
Van der Waals forces, also known as Dispersion forces, are the weakest type of molecular bonds. They are only formed through residual molecular attractions when molecules pass by each other. It doesn't even last long due to the uneven electron dispersion. It can be made stronger by adding more electrons in the molecule. This kind of molecular bonds appear in non-polar molecules such as carbon dioxide.
HOPE THIS HELPS!!!!!!!!!!!!!!
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The change that Hydrogen Bonds are most likely responsible for would be:
B). Causes salts to quickly dissolve in water.
As per the details provided, the hydrogen bonds are classified into the category of Van der Waals forces and the primary reason behind this has been that it leads salt to solvate immediately in the water. Amongst all the bonds, covalent bonds are characterized as the toughest while ionic bonds and hydrogen bonds are followed by it in terms of strength.The reason for which hydrogen bonds cause the change of allowing salts to dissolve immediately is that it illustrates a weaker strength of molecules due to its formation with residual uneven construction.Thus, option B is the correct answer.
Learn more about 'Covalent Bonds' here:
brainly.com/question/10777799
What type of energy is described as electrons moving in a circuit?
Answer:
Electrical energy (form of kinetic energy)
Explanation:
Tutorial Service is considered as what type of product?
Answer:
A tutorial, in education, is a method of transferring knowledge and may be used as a part of a learning process. More interactive and specific than a book or a lecture, a tutorial seeks to teach by example and supply the information to complete a certain task.
5. Determine the number of liters in 4.32 grams of water (H2O). Answer: --_ 5.37L H2O__
Answer:
4.32 [tex]\frac{1}{18.01}[/tex] ×[tex]\frac{22.4}{1}[/tex] = 5.37
Explanation:
22.4 is how many liters per mole. 18.01 is the mass of H2O.