1) divide each percentage by the relative atomic mass of the element
2) divide all results by the smallest number
3)multiply by a whole number to get the simplest whole number ratio (if necessary)
that is to say:
Na S O
32.37÷23 22.58÷32 45.05÷16
= 1.407 = 0.7056 = 2.816 (to 4 significant figures)
the smallest number here is 0.7056 so:
1.407÷0.7056 0.7056÷0.7056 2.816÷0.7056
=1.99 approx.2 = 1 3.99 approx. 4
here there is no need to carry out step 3 as ratio obtained is already a simplest whole number ratio
so empirical formula is: Na₂SO₄
<span>1) Humans have how many sets of teeth?
C) 4
2) Adults have how may permanent teeth?
B) 32
3) What type of food products make teeth stronger?
Cheese and Yogurt
4) What is the visible part of the tooth?
C) crown
5) What part of the tooth is harder than bone?
D) dentin
6) What part of the tooth is soft and contains the nerves?
A) pulp
7) What refers to the alignment of the teeth?
</span><span>
Occlusion</span><span>
8) The lower teeth protect what?
D) tongue
9) Malocclusion is the least common reason for referral to orthodontists.
False
10) Usually, malocclusion is hereditary.
True
11) Which type of malocclusion is commonly referred to as an overbite?
Class Two
12) Bacteria are living organisms than cause cavities.
True
13) What is the whitish film that grows on your teeth called?
Plaque
14) What is the best fighter of cavities?
Fluoride
Gingivitis is the inflammation of the
A) gums
16) Gingivitis is permanent.
False
17) Name 2 ways to fight gingivitis.
Proper Toothbrushing and Flossing
</span>Professional Dental Cleanings<span>
18) The cause of gum disease is
B) bacteria
19) Untreated, periodontitis will progress until your teeth loosen and fall out.
True
</span>
22 is a
23 is d
24 is c
I believe the answers are correct.
I'm not exactly sure which one but I do know that an acid and a base react in a aqueous solution to form water, so i would probably eliminate the ones that aren't aqueous solutions.
Answer:
4.43 g of Oxygen
Explanation:
As shown in Chemical Formula, one mole of Aluminium Sulfate [Al₂(SO₄)₃] contains;
2 Moles of Aluminium
3 Moles of Sulfur
12 Moles of Oxygen
Also, the Molar Mass of Aluminium Sulfate is 342.15 g/mol. It means,
342.15 g ( 1 mole) of Al₂(SO₄)₃ contains = 192 g (12 mole) of O
So,
7.9 g of Al₂(SO₄)₃ will contain = X g of O
Solving for X,
X = (7.9 g × 192 g) ÷ 342.15 g
X = 4.43 g of Oxygen
