A closed economy<span> is self-sufficient, meaning no imports are brought in and no exports are sent out, the goal being to provide consumers with everything they need from within the </span>economy's borders. An example would be how <span>Brazil's is an unusually </span>closed economy<span> as measured by trade penetration, with exports plus imports equal to just 27.6 per cent of GDP in 2013.</span>
Answer is: Cl and Na.
sodium and chlorine are in third period and they have very different properties. Sodium is solid metal and chlorine is gaseous nonmetal.
They form compound NaCl (Sodium chloride), because sodium lost one valence electron and form cation Na⁺, chlorine gain one electron and form anion Cl⁻.
Electron configuration of sodium atom: ₁₁Na 1s² 2s² 2p⁶ 3s¹.
Electron configuration of chlorine atom: ₁₇Cl 1s² 2s² 2p⁶ 3s² 3p⁵.
Other examples are metal-metal pairs and they do not form cation and anion.
Answer:
Indeed, most ionic compounds contain polyatomic ions. Well-known examples are sodium hydroxide (NaOH) with OH- as the polyatomic anion, calcium carbonate (CaCO3), and ammonium nitrate (NH4NO3), which contains two polyatomic ions: NH+ and NO3-.
Explanation:
hope it helps
Answer:
natural selection does not cause a species to change
Explanation:
I believe that's what it is
Answer:
Kinetic energy is directly proportional to mass
Explanation:
Kinetic energy is directly proportional to the mass of an object and also directly proportional to the square of the velocity of that object:
Notice that if we keep velocity constant and only increase the mass of a object, the kinetic energy of that object would increase, as we've already emphasized the direct relationship between the kinetic energy term and the mass term.
Let's take a simple example: assume that object 1 and object 2 are both moving at the same velocity but object 1 has a much lower mass than object 2. According to the equation, object 1 has lower kinetic energy. This object can then transform all of its kinetic energy into some other form, say, heat the ground. The heat transferred will be significantly lower than by the object 2 moving at the same velocity but having a much greater mass.
