Answer:
After the water has evaporated, the white crystals in the beaker have a mass of 20.0g.
The pieces of experimental evidence would best help the student to confirm that a new compound had not been made and that only a physical change occurred is of 20.0 g of white KCl crystals.
What are physical changes?Physical changes are defined as a modification to a sample of material when some of the substance's attributes change but the composition of the sample remains the same. The digestion of food, combustion, osmosis, and phase transitions are just a few examples of how these changes play a crucial role in our daily lives.
Crystals are defined as a solid substance whose elements such as atoms, molecules, or ions are grouped in a highly organized microscopic structure to create an all-pervasive crystal lattice. Crystals are formed when molecules in a liquid group together to stabilize when it starts to cool and solidify.
Thus, the pieces of experimental evidence would best help the student to confirm that a new compound had not been made and that only a physical change occurred is of 20.0 g of white KCl crystals.
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mention the three colours of Zanzibar .
Answer:
horizontal tricolor with three equal-sized stripes of blue, black and green.
Explanation:
hope this is what u want
Answer: ↓
Black and Vivid Cerulean,
About The Photos: This second Photo is the flag from the 2000's I believe, and the first Photo shows the 1964 flag.How many mL in 4 L of H2O?
Answer:
4,000 mL of H2O
If the actual yield of sodium chloride from the reaction of
8.3 g of sodium and 4.5 g of chlorine is 6.4 g, what is the percent yield?
Answer:
86%
Explanation:
Calculate the theoretical yield from the mass of each reactant. The lesser amount is the theoretical yield. Then use the following formula to calculate the percent yield: % yield = actual yield/theoretical yield X 100.
What is depicted in a molecular formula?
Answer:
Molecular formula describes about number of atoms of each constituent element present in any molecule.
Explanation:
Molecular formula describe about the number and type of atoms in any molecule. A molecular formula is not a chemical name but instead it is a chemical formula of a compound. A molecular formula consist of chemical symbols for constituent elements followed by numeric subscripts which tells us about number of atoms of each element present in a molecule. For example : Ammonia is a compound of nitrogen and hydrogen i.e NH₃ . As there is only one N atom so we have written only N in it's molecular formula. But as there are 3-H atoms so we have written subscript 3 in H symbol in it's molecular formula. Molecular formula does not tell us anything about shape of molecule .
Why do positive ions have a positive charge?
Answer:
Ions form when atoms gain or lose electrons. Since electrons are negatively charged, an atom that loses one or more electrons will become positively charged; an atom that gains one or more electrons becomes negatively charged. Ionic bonding is the attraction between positively- and negatively-charged ions.
what is the charge on a calcium (Ca) atom that contains 18e?
Answer:
Ca2+
Explanation:
Jack is melting butter in a pan. He observes a clear liquid with many solid particles floating in it. Based on Jack's observation, what conclusion can be made about butter?
Answer:
B.
Butter is a mixture of pure substances.
Explanation:
just poop and you will see
What do all the atoms of Group 1A elements have in common?
Type the correct answer in the box, Express the answer to three significant figures. Given: N2 + 3Cl2 + 2NC3, AH = 464 kJ/mol Use the given bond energies and the periodic table to calculate the energy change in the reaction. The AH when 85.3 grams of chlorine reacts in the given reaction is kilojoules.
Answer:
The given chemical reaction is:
Δ∑BE(reactants)-∑BE(products)
= {(941 kJ/mol) + (3 * 242 kJ/mol)} -[{2*(3*200 kJ/mol)}]
= 467 kJ/mol
Calculating the change in heat when 85.3 g chlorine reacts in the above reaction:
Moles of chlorine =
= 1.20 mol
Heat change when 1.20 mol chlorine reacts
=
Explanation:
Answer:
He is right tho not gone hold you
Explanation:
Which formula below can be used to calculate speed?
Speed = Volume ÷ Mass
Speed = Time ÷ Distance
Speed = Mass x Acceleration
Speed = Distance ÷ Time
Answer:
The answer is Speed= Distance ÷ Time
Explanation:
To work out what the units are for speed, you need to know the units distance and time.
What is the atomic number of an element that has seven protons and eight neutrons and seven electrons?
Answer:
Nitrogen has an atomic number of 7 (Z=7) because it has 7 protons in its nucleus. Some nitrogen atoms have an atomic mass number of 15 (A=15). A is the number of neutrons plus protons in the nucleus. However, we already know that there are 7 protons
Answer:
Atomic number = Number of protons = Number of electrons
Atomic number = 7
Determine the number of seconds in one week.
Answer:
604,800 seconds in a week
Explanation:
86,400 seconds in a day
86,400 × 7 = 604,800
Given a force of 100.00 N and an acceleration of 5 m/s2, what is the mass of the object?
Answer:
20 kgExplanation:
The mass of the object can be found by using the formula
[tex]m = \frac{f}{a} \\ [/tex]
f is the force
a is the acceleration
From the question we have
[tex]m = \frac{100}{5} = 20 \\ [/tex]
We have the final answer as
20 kgHope this helps you
how does the ocean affect the climate of nearby mountain ranges ?
give me a good paragraph ! for extra points pls
Answer:
Prevailing winds (sea breeze) from the ocean push warm moist air against the mountain & it moves up. As the moist air rises, it begins to get cooler and cooler due to the high altitude. ... Dry Air Since the air already lost its moisture, the humidity on this side is low & plants get very little water.
Explanation:
The oceans influence climate by absorbing solar radiation and releasing heat needed to drive the atmospheric circulation, by releasing aerosols that influence cloud cover, by emitting most of the water that falls on land as rain, by absorbing carbon dioxide from the atmosphere and storing it for years t
When something heats up it moves faster when something close down it moves slower
Answer:
Yes
Explanation:
Answer:
THATS WHAT SHE SAID
Explanation:
Can anybody help me asap pls
Answer:
Here is ur answer...
Explanation:
2) Half-filled d orbital increases the stability of the element.
With the aid of a balanced chemical equation explain Chemical Reactions and the Types Of Chemical Reaction
Answer:
Answers
1.)reactants: nitrogen and hydrogen; product: ammonia.
2.)reactants: magnesium hydroxide and nitric acid; products: magnesium nitrate and water.
3.)N 2 + 3H 2 → 2NH 3
4.)Mg(OH) 2 + 2HNO 3 → Mg(NO 3) 2 + 2H 2O.
5.)2NaClO 3 → 2NaCl + 3O 2
6.)4Al + 3O 2 → 2Al 2O 3
7.)N 2(g) + 3H 2(g) → 2NH 3(g)
Explanation:
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A chemical reaction is a process in which atoms are rearranged to form new molecules or substances. During a chemical reaction, chemical bonds are broken and formed, resulting in the transformation of reactant molecules into product molecules. The reactants and products of a chemical reaction are characterized by their chemical formulas, which describe the types and numbers of atoms present in the molecules.
A balanced chemical equation is a written representation of a chemical reaction that shows the reactants on the left side of the equation and the products on the right side. The equation is balanced by adjusting the coefficients (the numbers in front of the chemical formulas) so that the number of atoms of each element is the same on both sides of the equation. This ensures that the law of conservation of mass is obeyed, which states that matter cannot be created or destroyed during a chemical reaction.
There are several types of chemical reactions, including:
Decomposition reactions: These reactions involve the breakdown of a single compound into two or simpler substances. An example of a decomposition reaction is the thermal decomposition of water to form hydrogen and oxygen gases:
2H2O (l) -> 2H2 (g) + O2 (g)
Displacement reactions: These reactions involve the replacement of one element with another element in a compound. An example of a displacement reaction is the reaction of zinc with hydrochloric acid to form zinc chloride and hydrogen gas:
Zn (s) + 2HCl (aq) -> ZnCl2 (aq) + H2 (g)
Redox reactions: These reactions involve a transfer of electrons from one species to another. An example of a redox reaction is the reaction of magnesium with oxygen to form magnesium oxide:
2Mg (s) + O2 (g) -> 2MgO (s)
Combination reactions: These reactions involve the combination of two or more substances to form a single compound. An example of a combination reaction is the reaction of hydrogen and oxygen to form water:
2H2 (g) + O2 (g) -> 2H2O (l)
Acid-base reactions: These reactions involve the transfer of a proton from an acid to a base. An example of an acid-base reaction is the neutralization of hydrochloric acid with sodium hydroxide to form water and sodium chloride:
HCl (aq) + NaOH (aq) -> H2O (l) + NaCl (aq)
Bases form __________ ions in water.
a.
hydrogen
c.
positive
b.
hydroxide
d.
both a and c
Answer:
d
Explanation:
Answer:
a. hydrogen
Explanation:
People's actions can cause air pollution. People can plant trees to help reduce air pollution.
How does planting trees help reduce air pollution?
O A Trees take in nitrogen and dust.
B. Trees block sunlight from reaching the ground.
O c Trees produce oxygen and take in carbon dioxide.
D. Trees add nutrients to the soil that other living things need
Answer:
c
Explanation:
What part does chlorophyll play in photosynthesis?
A. It transports sugar and water to plant leaves
B. It uses suns energy to “cook”water and carbon dioxide
C. It drinks water from the soil around the roots of the plant
D. Breathes the air around the plants and gets carbon dioxide
Answer:
B
Explanation:
it uses the process of the light reaction stage and Calvin cycle to trap sunlight in the day and make food at night
Answer:
I think the answer is A or B
Please help! Please!!!
Look at the picture down below to answer the question!
>>Select the 2 that apply.
Q: An unsaturated hydrocarbon is represented by which structural formula(s)?
>>Choose two from the picture below that matches with the question above!
Answer:
A and D
Explanation:
unsaturated hydrocarbons have double or triple bonds
6. Why does DNA need to be organized into chromosomes before cell division?
The DNA would be too difficult to separate without this organization.
The DNA would take up too little space without this organization.
The DNA would be pulled apart rapidly without this organization.
The DNA would be broken without this organization.
Answer:
The DNA would be too difficult to separate without this organization.
Explanation:
DNA is usually wrapped loosely, but when ready to divide it wraps tighter. It's so each chromosome is a distinct unit. When the cell divides one copy goes to each of the resulting cells. If not lined up properly sereve genetic issues can occur. Chromosome alignment makes the process more efficient.
Which statements apply to density? Check all that apply.
O Density is a chemical property of an object.
The density of an object is constant.
Density is a derived unit of measure.
Density is the sum of the mass and volume of an object.
The density of an object determines whether it will sink or float.
Answer:
the density of an object determines whether it will sink or float
Answer:
Its B,C,E
Explanation:
parts of Earth and its atmosphere where there is life
Answer:
stratosphere
Explanation:
The stratosphere is crucial to life on Earth because it contains small amounts of ozone, a form of oxygen that prevents harmful UV rays from reaching Earth.
When placed in distilled water, the pH of metal oxides will be?
Less than 7
Equal to 7
greater than 7
neutral
When placed in distilled water, the pH of metal oxides will be greater than 7. The correct option is C.
What are metal oxides?Metal oxides are crystalline solids containing both a metal cation and an oxide anion. In most cases, they react with water to form bases or with acids to form salts.
Metal oxides are compounds that contain two elements, namely a metal and an oxygen atom. Examples include sodium oxide (Na2O), magnesium oxide (MgO), calcium oxide (CaO), and others.
When metal oxides react with dilute acids, they form salt and water, demonstrating that they are basic.
Metal oxides are alkaline. When we dissolve them in water, we get solutions with pH values higher than 7. The reaction between a nonmetal and oxygen produces nonmetal oxides. Nonmetal oxides are highly acidic.
Thus, the correct option is C.
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find the co valance of c in C2S2
Answer:
A better term than
covalency
might be
molecularity
. Molecular species TEND to have reduced melting points and boiling points with respect to non-molecular species. Non molecular species, which include sodium chloride, and graphite, and diamond, thus have much HIGHER melting points than methane or ethane, or water, which are composed of discrete molecules.
Explanation:
30 POINTS!! ILL MAKE BRAINLIEST!!
Thanks! also that's a lot use a calculator.!
Calculate the new volume if a 13.40 L of a gas at a pressure of 1.51 atm is subject to a new pressure of 65 mmHg.
Answer:
V₂ = 238.05 L
Explanation:
Given data:
Final volume = ?
Initial volume = 13.40 L
Initial pressure = 1.51 atm
Final pressure = 65 mmHg ( 65/760 = 0.085 atm)
Solution:
The given problem will be solved through the Boyle's law,
"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
Now we will put the values in formula,
P₁V₁ = P₂V₂
1.51 atm × 13.40 L = 0.085 atm × V₂
V₂ = 1.51 atm × 13.40 L / 0.085 atm
V₂ = 238.05 L
Suppose an environmental change that causes the soil color to become much different occurs in both environments. Which of the following is true?
A.
Population 1 is more likely to adapt and survive than population 2 because there is more variation related to body color in population 1.
B.
The individuals in both populations will adapt within their lifespans to exhibit a darker body color because this will increase their ability to survive.
C.
Population 2 is more likely to adapt and survive than population 1 because there is more variation related to body color in population 2.
D.
Both populations are equally as likely to adapt and survive because both populations exhibit the same level of body color variation.
Answer: the answer is A
Explanation:
State and explain each law of motion.
Answer:In the first law, an object will not change its motion unless a force acts on it. In the second law, the force on an object is equal to its mass times its acceleration. In the third law, when two objects interact, they apply forces to each other of equal magnitude and opposite direction
Explanation:
Answer:
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Explanation:
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