Answer:
Fluoride is commonly used in dentistry to strengthen enamel, which is the outer layer of your teeth. Fluoride helps to prevent cavities. It’s also added in small amounts to public water supplies in the United States and in many other countries. This process is called water fluoridation.
Explanation:
<span>2.40 - 1.68 =0.72 g of oxigen
moles = 0.72/16 g/mol=0.045
moles x = 1.68/ 55.9=0.03
0.03/0.03 = 1 = x
0.045 / 0.03 = 1.5 = O
to get whole numbers multiply by 2
x2O3
X2O3 +3 CO = 2 X + 3 CO2</span>
Answer:
+ axit
CH2=CH-CH2-COOH,
CH3-CH=CH-COOH (tính cả đồng phân hình học)
CH2=C(CH3)-COOH.
+ este
HCOOCH=CH-CH3 (tính cả đồng phân hình học)
HCOO-CH2-CH=CH2,
HCOOC(CH3)=CH2.
CH3COOCH=CH2
CH2=CH-COOCH3
I think the answer is letter B.
