Answer:
Step-by-step explanation:
Silicon is a member of Group 14 (IVA) in the periodic table. The periodic table is a chart that shows how chemical elements are related to one another. Silicon is also part of the the carbon family. Other carbon family elements include carbon, germanium, tin, and lead. Silicon is a metalloid, one of only a very few elements that have characteristics of both metals and non-metals.
Silicon is the second most abundant element in the Earth's crust, exceeded only by oxygen. Many rocks and minerals contain silicon. Examples include sand, quartz, clays, flint, amethyst, opal, mica, feldspar, garnet, tourmaline, asbestos, talc, zircon, emerald, and aquamarine. Silicon never occurs as a free element. It is always combined with one or more other elements as a compound.By the early 1800s, silicon was recognized as an element. But chemists had serious problems preparing pure silicon because it bonds (attaches) tightly to oxygen. It took chemists many years to find out how to separate silicon from oxygen. That task was finally accomplished in 1823 by Swedish chemist Jons Jakob Berzelius (1779-1848).
Silicon's most important application is in electronic equipment. Silicon is one of the best materials from which to make transistors and computer chips. The total weight of silicon used for this purpose is relatively small. Much larger amounts are used, for example, to make metal alloys. An alloy is made by melting and mixing two or more metals. The mixture has properties different from those of the individual metals.
Answer:
x = 52
y = 38
Step-by-step explanation:
Angle x is supplementary to a 128º angle.
Supplementary angles add to 180
x+128 = 180
Subtract 128 from each side
x+128-128 = 180-128
x =52
Angle x and y are complementary.
Complementary angles add to 90
x+y =90
52+y =90
Subtract 52 from each side
52-52 +y = 90-52
y = 38
4x^2 + 2x = -9
4x^2 + 2x + 9 = 0
remember that the form of quadratic is ax^2 + bx + c = 0
so
a = 4
b = 2
c = 9
Answer:
13 carnations
Step-by-step explanation:
Assuming you meant 2/5 because 2.5 would mean there are more roses in the vase than there are flowers in the vase, heres how to solve this.
Understanding
Each fraction is referring to "flowers" not "remaining flowers" and as such each time we will be comparing to the total.
2/5 of the total flowers are roses. This is written in words as for every 5 flowers two are roses, which means we will multiply 2 by how many sets of five we have in 30 flowers.
(30/5) x 2 =
(6) x 2 = 12 roses
Though with fractions its written as 30/1*2/5 which is the same as (30 x 2)/5
60/5 = 12 roses
Following this logic for every 6 flowers one is a daisy.
30/1 * 1/6 = (30 x 1)/6 = 30/6 = 5 daisies
Because the rest are carnations we want to subtract the amount of daisies and roses from the total amount of flowers to find the remaining flowers.
30 - 5 - 12 = 13 carnations
Hope this helps,
