Hey there!
Your answer is D. salt water
A mixture has more than one substance.
Salt water is made up of multiple different substances, salt (NaCl) and water (H₂O).
Carbon dioxide (CO₂), water vapor (H₂O), and oxygen gas (O₂) are each just one substance.
Hope this helps!
Explanation:
A covalent bond is formed when an element shares its valence electron with another element. This bond is formed between two non metals.
An ionic bond is formed when an element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element and the element which accepts the electrons is known as electronegative element. This bond is formed between a metal and an non-metal.
Chlorine and potassium atoms form ionic bonds: Ionic bond is formed when there is complete transfer of electron from a highly electropositive metal to a highly electronegative non metal. Electronegativity difference = electronegativity of chlorine - electronegativity of potassium = 3-0.8 = 2.2
Carbon atoms form non-polar covalent bonds with nitrogen atoms : Non-polar covalent bond is defined as the bond which is formed when there is no difference of electronegativities between the atoms. Electronegativity difference = electronegativity of nitrogen - electronegativity of carbon= 3.0-2.5 = 0.5
Oxygen forms polar covalent bonds with phosphorus: A polar covalent bond is defined as the bond which is formed when there is a difference of electronegativities between the atoms. Electronegativity difference = electronegativity of oxygen - electronegativity of phosphorous = 3.5- 2.19 = 1.31
Hi there! Air and sunlight can definitely be reused. Those are abundant and renewable resources. Therefore, A and D are eliminated. There is a limited amount of water, however, it's impossible to run out of it to the point that there's no more on Earth. C is out. The only answer choice that makes sense is coal, because it's a nonrenewable resource, and it takes millions of years to make more of. It's a fossil fuel, so once we use them up, we can't get anymore during our lives. The answer is B: coal.
So the empirical formula is Mg3N2
Explanation:
Tc - 99 is technetium 99.
It is a radioactive element that decays spontaneously. It has a half-life of 211,000 years and decays to stable ruthenium.
- On the periodic table, it has an atomic number of 43;
Mass number = 99
Atomic number = number of protons = number of electrons in atom
Number of protons in Tc is 43
electron is 43
Mass number = number of protons + number of neutrons
Number of neutrons = mass number - number of protons = 99-43 = 56
learn more:
Atomic number brainly.com/question/2057656
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