1. Ge
2. Fe
3. Zn
Remember, electronegativity decreases down a group (vertically) and increases across a period (horizontally) on the periodic table. :)
Answer:
A. Optical fibers transmit light signals in high-speed communications.
Explanation:
You didn't include the image, but it probably showed light bouncing off the sides as in the diagram below.
It demonstrates how optical fibers transmit light signals in high-speed communications.
B is wrong. Satellites communicate by radio waves.
C is wrong. Solar cells convert light energy to
D is wrong. Power plants transmit electrical energy to homes through copper wires.
The dependent variable is plant height.
The <em>dependent variable</em> (plant height) is the <em>property that changes</em> as a result something the scientist does.
The <em>independent variable</em> is the <em>property that the scientist changes</em> systematically (the amount of CO_2) to see its effect.
The <em>number of plants</em> and the <em>types of plants</em> are <em>uncontrolled variables</em>. They may or may not affect the heights of the plants.
Answer:
Water acts as a base in the presence of a strong acid
Explanation:
Water,being an amphoteric compound, can act both as an acid and as a base.
In the presence of an acid , water acts as a base but in the presence of a base, water acts as an acid.
Answer:
Molality = 8.57 m
Explanation:
Given data:
Molarity of solution = 5.73 M
density = 0.9327 g/mL
Molality of solution = ?
Solution:
Molality = moles of solute / kg of solvent.
Kg of solvent:
Mass of 1 L solution = density× volume
Mass of 1 L solution = 0.9327 g/mL × 1000 mL
Mass of 1 L solution = 932.7 g
Mass of solute:
Mass of 1 L = number of moles × molar mass
Mass = 5.73 mol × 46.068 g/mol
Mass = 263.97 g
Mass of solvent:
Mass of solvent = mass of solution - mass of solute
Mass of solvent = 932.7 g - 263.97 g
Mass of solvent = 668.73 g
In Kg = 668.73 /1000 = 0.6687 Kg
Molality:
Molality = number of moles of solute / mass of solvent in Kg
Molality = 5.73 mol / 0.6687 Kg
Molality = 8.57 m