Answer:
Semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.
Explanation:
A semiconductor can be defined as a crystalline solid substance that has its conductivity lying between that of a metal and an insulator, due to the effects of temperature or an addition of an impurity. Semiconductors are classified into two main categories;
1. Extrinsic semiconductor.
2. Intrinsic semiconductor.
The statement which best describes the electrical conductivity of metals and semiconductors is that semiconductors are poor conductors at low temperatures, but their resistance decreases with increasing temperature.
This ultimately implies that, semiconductors are typically an insulator (poor conductor) at low temperatures and a good conductor at high temperatures.
Additionally, conduction involves the transfer of electric charge or thermal energy due to the movement of particles. When the conduction relates to electric charge, it is known as electrical conduction while when it relates to thermal energy, it is known as heat conduction.
Answer:
4 C3H5N3O9 ------> 6N2 + O2 + 10H2O + 12CO2
Explanation:
Nitroglycerin has a chemical formula C3H5N3O9. The balanced chemical equation is as follows:
4 C3H5N3O9 ------> 6N2 + O2 + 10H2O + 12CO2
We suppose that in a reaction, 44g of carbon dioxide is produced. The mass of nitroglycerin that must have reacted will be calculated as under:
Molecular mass of Nitroglycerin = 227g/mol
Molecular mass of Carbon dioxide = 44g/mol
No. of moles of carbon dioxide produced = 44/44 = 1 mole produced.
Now, from balanced chemical equation, we can see that
12 moles of carbon dioxide are produced by = 4 moles of nitroglycerin.
1 mole of carbon dioxide is produced by = 4/12 = 1/3 moles of nitroglycerin.
Mass of nitroglycerin which produced 1 mole of carbon dioxide = 1/3 x 227 = 75.666 grams.
Plants obtain energy from the sun during photosynthesis and pass it along the food chain.
<h3>What is a model?</h3>
A model is a representation of reality. We use models to understand what the real situation of things is like.
Let us recall that plants are the producers in the ecosystem. Energy flow from plants to animals. Plants obtain energy via the reaction 6CO2 + 6H2O --->C6H12O6 + ATP. This energy is passed along the food chain as organisms feed on each other.
Learn more about models: brainly.com/question/14281845
Answer: The number 4 indicates 4 electrons.
Explanation: We are given an electronic configuration, which is:
Here,
- The letters denote the sub-shells of an element.
- The numbers written before the letters which are 1, 2 and 2 represents the Principle Quantum Number and these represents the energy level of the sub-shells.
- The number which are written in the superscripts which are 2, 2 and 4 denotes the electrons which are present in the sub-shell.
Hence, 4 indicates 4 electrons present in 2p sub-shell.
<span>Answer: 56.6 moles
Explanation:
28.3 moles of Pb would produce twice as much moles as Ag.
28.3 X (2moles Ag/ 1 mol Pb) = 56.6 moles of Ag.</span>
