In the chemical reaction below, calcium (Ca) and water (H2O) react to form calcium hydroxide (Ca(OH)2) and hydrogen gas (H2).
Ca (s) + 2H2O (l) → Ca(OH)2 (aq) + H2 (g)
Calcium and water are the reactants in this chemical reaction, whereas calcium hydroxide and hydrogen gas are the products that are formed. Once the reaction reaches completion,
Finish The Sentence...
A.
the products of the reaction will have changed back into the reactants.
B.
the total mass of the products will be greater than the original mass of the reactants.
C.
the total mass of the products will be equal to the original mass of the reactants.
D.
the total mass of the products will be less than the original mass of the reactants.
compounds with high melting points have _____
A.covalent bonds
B. metallic bonds
C. ionic bonds
D. no chemical bonds
Answer:
C) Ionic bonds
Explanation:
The ionic bonds are the strongest bond, it occurs when a metal donates electrons and a nonmetal gain these electrons. They'll be together by electrostatic force.
Metallic bonds it the second strongest bond, it occurs between metals, which loses electrons. It's an electrostatic force, but weaker than the ionic compound because it occurs between the cation and the electron.
Covalent bonds are the weakest bond. It happens between metals and nonmetals, or nonmetals and hydrogen or between atoms of hydrogen. The force that joins the atoms depends on the polarity of the molecule. Polar molecules have dipole forces, nonpolar molecules, induced dipole forces. Also, hydrogen makes special dipole forces with nitrogen, oxygen, and fluorine, called hydrogen bond.
As the stronger is the force, as difficult it will be to break it. So, ionic bonds will demand more energy to become gas, and have high melting points.
Compounds with high melting points have [tex]\boxed{{\text{C}}{\text{. ionic bonds}}}[/tex].
Further Explanation:
The attraction between different atoms, molecules and ions is known as a chemical bond. Such bonds are responsible for the formation of chemical compounds.
Ionic bond
It is formed by the interaction of a metal with a non-metal. Metals are electropositive in nature so they have the tendency to lose electrons whereas non-metals tend to gain electrons due to their high electronegativity. Metal atoms form cations by loss of electrons and non-metals become anions with the gain of electrons.
Covalent bond
It is formed by the mutual sharing of electrons between the bonded atoms. It is also known as a molecular bond. Such bonds usually exist between two or more non-metals.
Metallic bonds
These are formed between metal atoms and metallic solids are produced. These are good conductors of electricity due to the presence of delocalized electrons. Copper, gold, zinc are examples of metallic solids.
An ionic bond is the strongest bond, followed by metallic bond and covalent bond is the weakest among the three given bonds. A large amount of energy is required to break ionic bonds as compared to the other two bonds so compounds with ionic bonds have high melting points. Therefore option C is correct.
Learn more:
Identification of ionic bonding: https://brainly.com/question/1603987 What type of bond exists between phosphorus and chlorine? https://brainly.com/question/81715Answer details:
Grade: High School
Subject: Chemistry
Chapter: Ionic and covalent compounds
Keywords: chemical bond, melting points, metallic bond, ionic bond, covalent compound, interactions, metals, nonmetals, cations, anions, mutual sharing of electrons.
a scoop of baking soda is added to a beaker containing vinager.the baking soda disapears and bubbles are observed.this is an example of an change
Question 1: Define the terms hypothesis, independent variable, dependent variable, and a controlled variable in your own words.
Question 2: We discussed the importance of having only one independent variable, but trying to test more than one independent variable is an error many people make. In the following experiment, identify the errors that the experimenter made and summarize a valid way to test his research question: What cooking spray best keeps food from sticking to a pan? In the morning, Dan uses grapeseed oil to cook eggs for breakfast; for lunch, he uses vegetable oil spray to coat a muffin tray and cooks cornbread to eat with his chili; for dinner, he uses olive oil to pan cook a hamburger patty.
pls help will give crown to best answer
why is the solubility of a neutral organic compound unaltered by exposure to aqueous acid or base?
What are some catchy projects titles for the question, "What liquids cause the most tooth decay?"
When determining an element's identity, what is the most important subatomic part to examine?
A) electrons
B) neutrons
C) valence electrons
D) protons
What is the STM in science
STM in science stands for Scanning Tunneling Microscope, a device that allows visualization of atomic-level details on surfaces, revealing individual atoms and contributing to nanotechnology research.
Explanation:In science, STM refers to a Scanning Tunneling Microscope, an instrument for imaging surfaces at the atomic level. An STM uses a sharp tip that scans a surface at a constant potential. As the tip moves close to surface atoms, electrons tunnel from the surface to the tip, creating a current that varies based on the distance between the tip and the surface. This tunneling-electron current is monitored and used to construct an image of the specimen with atomic-scale resolution. With an STM, scientists can literally see individual atoms, such as those on a sheet of gold, and structures like carbon nanotubes, providing profound insights into the physical world at the nanoscale.
What is a common characteristic of the transitions elements?
a glass marble has a mass of 18.5 g and a volume of 6.45 cm^3
The density of the glass marble is 2.87 [tex]g/cm^3[/tex].
Given the following data:
Mass of glass marble = 18.5 gramsVolume of glass marble = 6.45 [tex]cm^3[/tex]In this exercise, you're required to determine the density of the glass marble.
Density can be defined as mass per unit volume of an object.
Mathematically, the density of an object is given by the formula;
[tex]Density = \frac{Mass}{Volume}[/tex]
Substituting the given parameters into the formula, we have;
[tex]Density = \frac{18.5}{6.45}[/tex]
Density = 2.87 [tex]g/cm^3[/tex]
Therefore, the density of the glass marble is 2.87 [tex]g/cm^3[/tex].
Read more: https://brainly.com/question/18320053
Neon is an example of a(n): A. Alkali Metal B. Noble Gas C. Halogen D. Rare Earth Metal
When you blow dry your hair is it physical or chemical change
why do you think different liquids have different freezing points
Most enzymes in living things are made up of __________.
A. carbohydrates
B. lipids
C. proteins
D. nucleic acids
Answer:
The correct answer is C.
Explanation:
Enzymes are proteins that catalyze chemical reactions in living things. Enzymes are catalysts, so they are substances that without being consumed in a reaction significantly increase the speed. They do not make impossible reactions feasible but accelerate those that could spontaneously occur, increasing their speed when reacting.
Have a nice day!
In this forest, trees block much of the sunlight from reaching the ground. The branches of trees grow up and out to reach as much sunlight as they can. Which challenge of life does this example represent?
why is mitosis important to all living things
science question down below hurry
in a chemical reaction 48.6 grams of magnesium reacts with 32.0 grams of oxygen to form magnesium oxide how many grams of magnesium oxide would be produced from this reaction
A) 82.6 grams
B) 80.6 grams
C) 16.6 grams
D) 18.6 grams
please help
balance this equation
Cu(NO3)2➡️CuO+NO2+O2
Final answer:
The balanced chemical equation for the decomposition of copper(II) nitrate into copper(II) oxide, nitrogen dioxide, and oxygen is 2 Cu(NO3)2 ➔ 2 CuO + 4 NO2 + O2. This illustrates the conservation of mass by ensuring equal numbers of each type of atom on both sides of the equation.
Explanation:
The question you've asked pertains to balancing the chemical equation Cu(NO3)2 ➔ CuO + NO2 + O2. This process involves ensuring that the number of atoms for each element is the same on both sides of the equation.
To balance this equation, we start with the given substances and adjust the coefficients (the numbers in front of the chemical formulas) to make sure the atoms are balanced. After several steps of balancing, we arrive at the balanced equation:
2 Cu(NO3)2 ➔ 2 CuO + 4 NO2 + O2
This equation indicates that 2 moles of copper(II) nitrate decompose to form 2 moles of copper(II) oxide, 4 moles of nitrogen dioxide, and 1 mole of oxygen gas. The balancing process takes into account the conservation of mass, which states that atoms are neither created nor destroyed in a chemical reaction.
A student dissolved a sample in hexane, spotted it on to a TLC plate and eluted using ethyl acetate. After visualizing the TLC plate under a UV lamp, the student found their sample had two spots corresponding to Rf values of 0.31 and 0.85. They ran the TLC plate again, this time dissolving the compound in dicholoroacetic acid and using ethyl acetate as the eluent. What will be the Rf values for each spot?
1) Consider the following silica gel TLC plate of compounds A, B, and C developed in hexanes:
Determine the Rf values of compounds A, B, and C run on a silica gel TLC plate using hexanes as the solvent.Which compound, A, B, or C, is the most polar?What would you expect to happen to the Rf values if you used acetone instead of hexanes as the eluting solvent?How would the Rf values change if eluted with hexanes using an alumina TLC plate?Show answer
2) You are trying to determine a TLC solvent system which will separate the compounds X, Y, and Z. You ran the compounds on a TLC plate using hexanes/ethyl acetate 95:5 as the eluting solvent and obtained the chromatogram below. How could you change the solvent system to give better separation of these three compounds?
Show answer
3) After a rather lengthy organic chemistry synthesis procedure, a student ran the product of the reaction on a TLC plate and obtained the result below. What might he/she have done wrong, if anything?
Show answer
4) A student spots an unknown sample on a TLC plate. After developing in hexanes/ethyl acetate 50:50, he/she saw a single spot with an Rf of 0.55. Does this indicate that the unknown material is a pure compound? What can be done to verify the purity of the sample?
Show answer
5) Consider a sample that is a mixture composed of biphenyl, benzoic acid, and benzyl alcohol. The sample is spotted on a TLC plate and developed in a hexanes/ethyl acetate solvent mixture. Predict the relative Rf values for the three compounds in the sample.
Show answer
6) Plate A, below, represents the TLC chromatogram of a compound run in hexanes. The same compound was then spotted on a large TLC plate and again run in hexanes. Which TLC plate, B, C, or D, correctly represents how far the compound would run on the longer plate?
Show answer
Back to TLC
Original content © University of Colorado at Boulder, Department of Chemistry and Biochemistry.The greeks believed that fire was a state of matter. how did atomists describe fire?
Answer: atomists before Leucippus and Democritus described fire as being one of the four origins of matter, but Democritus and Leucippus described fire as being just likeeverything else and being composed of atoms.
Explanation:
I am a cold planet on the surface but hot at my core. There are 11 rings that circle me. You will find 21 moons in orbit around me. I rotate on my side. Which planet am I? A.
Pluto
B.
Jupiter
C.
Saturn
D.
Uranus
What is the balanced net precipitation reaction for BaCl2 and KOH?
Final answer:
The balanced net precipitation reaction for BaCl₂ and KOH results in solid barium hydroxide and potassium chloride in solution, with the net ionic equation being Ba²⁺(aq) + 2OH⁻(aq) → Ba(OH)₂(s)
The balanced net precipitation reaction between aqueous barium chloride (BaCl2) and potassium hydroxide (KOH) involves a double displacement reaction where the cation of one reactant (Ba2+ from BaCl2) combines with the anion of the other reactant (OH- from KOH) to form an insoluble product, barium hydroxide (Ba(OH)2).
The complete balanced equation is:
BaCl₂(aq) + 2KOH(aq) → Ba(OH)₂(s) + 2KCl(aq)
The net ionic equation, which shows only the species that change during the reaction, is:
Ba²⁺(aq) + 2OH⁻(aq) → Ba(OH)₂(s)
This equation is balanced both in terms of atoms and electric charge, with barium ions and hydroxide ions forming barium hydroxide, which precipitates out of the solution as a solid.
When two liquids are combined and form a solid (but didn't freeze) the solid that was formed is called
Which statement is true about a liquid but not a gas? It will change shape and take the shape of its container. It has more internal energy than the solid state. It allows particle to move past each other relatively easily. It has close to a constant volume as pressure is applied to it.\
Answer:
d
Explanation:
A 0.5376 g sample of an unknown compound is found to contain 0.3044 g of carbonate. Could this compound be calcium carbonate?
science question down below
A student conducted an experiment to test whether talking to plants would help them to grow faster. The student talked to one group of plants and hand watered them. The student did not talk to the other group of plants and used sprinklers. After three weeks, the plants that were spoken to showed much more growth than the plants that were not. Based on the results of this experiment, which is the best conclusion? Talking to plants may or may not help plants grow faster because three weeks is not enough time to tell. Talking to plants may or may not help plants grow faster because the amount of water given was likely different for each group. Talking to plants does not help plants grow faster because the experiment did not involve enough groups of plants to determine this. Talking to plants does help plants grow faster because those plants showed more growth.
Answer is: Talking to plants may or may not help plants grow faster because the amount of water given was likely different for each group.
The scientific method is a process for experimentation that is used to explore observations.
Steps of the scientific method:
1) ask a question about something that is observed.
2) do background research. It this ecample, research is not good enough, because there are teo variables (talking to plants and amount of water).
3) construct a hypothesis, an attempt to answer questions with an explanation that can be tested.
4) test of hypothesis.
5) analyze collected data and draw a conclusion.
What happens to the sample's reported water content if the salt decomposes yielding a volatile product?
The decomposition of salt yielding a volatile product can increase the reported water content of a sample in volatilization gravimetry, due to the attribution of the mass loss of the volatile product to water content.
When a sample's salt decomposes, yielding a volatile product, the reported water content of the sample can be affected. In volatilization gravimetry, the sample undergoes thermal or chemical decomposition, which leads to a change in mass resultant from the loss of volatile material. If the decomposition of the salt generates a volatile product, such as water vapor, this will lead to an erroneously high water content measurement since the volatile product is included in the total mass loss that is attributed to water content.
The temperatures used in drying the sample affect the results. Drying the sample at a lower temperature (103-105°C) could result in the retention of some occluded water, whereas drying at a higher temperature (180°C) may release occluded water but also cause a greater loss of substances like carbonates. If salts like chlorides and nitrates decompose, they may form volatile products that could escape, thereby falsely increasing the measurement of the water content.
To ensure accurate evaluations, it's essential to understand the decomposition products and use specialized equipment to trap and weigh any volatile products. This allows for a more precise measurement of the true water content of the sample.