First one because Common synthetic materials are nylon, acrylic, polyester, carbon fiber, rayon and spandex. Synthetic materials are made from chemicals and are usually based on polymers. They are stronger than natural and regenerated materials.
The periodic trend of reactivity depends on whether the elements are metals or nonmetals. For metals, reactivity increases down a group and from right to left across a period. Nonmetals do the opposite. For nonmetals, reactivity increases up a group and from left to right across a period. Therefore, the rank is as follows:
Fluorine
Selenium
Neon
Hope this answers the question. Have a nice day.
Answer:
The glass of water weigh once the antacid pill has dissolved will be less than the 179 grams due to evolution of carbon dioxide.
Explanation:
Mass of effervescent antacid pill = 4.00 g
Mass of water = 85 g
Mass of glass = 90 g
Total mass of the substances together : 4.00 g + 85 g + 90 g = 179 g
Effervescent antacid pill , moment it get dissolved in water carbon dioxide gas is evolves and escape from the solutions.
This means that mass of the weight of the glass of water with antacid dissolved in it will be less than 179 grams.
C) Weathering can be chemical or physical; deposition
is only chemical
Answer:
The balanced equation is given below:
SiO2 + 4HF —> SiF4 + 2H2O
The coefficients are 1, 4, 1, 2
Explanation:
The equation for the reaction is given below:
SiO2 + HF —> SiF4 + H2O
The above equation can be balance by as follow:
There are 4 atoms of F on the right side and 1 atom on the left side. It can be balance by putting 4 in front of HF as shown below:
SiO2 + 4HF —> SiF4 + H2O
Therefore are 4 atoms of H on the left side and 2 atoms on the right side. It can be balance by putting 2 in front of H2O as shown below:
SiO2 + 4HF —> SiF4 + 2H2O
Now the equation is balanced.
