I think that the sun is the center of the universe, not a human being. Everything revolves around the sun, not someone. U know when to sleep, when the time is, and when to wake up based on the sun. All the planets revolve around it. This is why I think the sun is the center of the universe, not a human being.
Answer is D relative distance
Answer
a) Group 16
b) Group 1
c) Group 15
d)
e)
f) Sodium
g) Oxygen
h) Phosphorus
Procedure
Using the periodic table below identify the elements. The periodic table organizes elements in a way that reflects their number and pattern of electrons. The table places elements into columns—groups—and rows—periods.
An element’s column number gives information about its number of valence electrons and reactivity. In general, the number of valence electrons is the same within a column and increases from left to right within a row. Applies only for groups 1,2, 13-18 (remembering that from 13 to 18 the last number is the valence).
Answer:
- <em>The molar concentraion is </em><u>0.74 M</u>
Explanation:
<u>1) Data:</u>
a) % w/v = 2.5%
b) compound: H₂O₂ (from a table molar mass = 34.0147 g/mol)
c) M = ?
<u>2) Formulae:</u>
a) % w/v = (mass of soulte / volume of solution) × 100
b) numer of moles, n = mass in grams / molar mass
c) M = number of moles of solute / liters of solution
<u>3) Solution:</u>
a) T<u>ake a base of 100 ml of solution (0.100 liter)</u>:
- %w/v = 2.5% = 2.5 g solute / 100 ml solution
- mass of solute = 2.5 g / 100 ml × 100 ml = 2.5 g
b) <u>Calculate the number of moles of solute, n</u>:
- n = mass in grams / molar mass = 2.5 g / 34.0147 g/mol = 0.0735 mol
c) <u>Calculate the molarity, M</u>:
- M = n / V in liter = 0.0735 mol / 0.100 liter = 0.735 M
Round to two significant figures: 0.74 M ← answer
