1. The answer is option E, that is None of the above is correct.
As a polymer becomes more crystalline,
its melting point doesn't decreases, its density doesn't decreases, its stiffness doesn't decreases and its yield stress doesn't decreases.
2. The answer is option B, that is the molecules are arranged in sheets, with their long axes parallel and their ends aligned as well.
In the smectic A liquid-crystalline phase, molecules are arranged in sheets, with their long axes parallel and their ends aligned as well.
3. For a substitutional alloy to form, the two metals combined must have similar atomic radii and chemical bonding properties.
Answer:
The Bronsted-Lowery acid is H2O
The Bronsted-Lowery base is CO3
The conjugate acid is HCO3
The conjugate base is OH
Explanation:
Molocules that lose a hydrogen in a reaction act as an acid, and those that recieve one act as a base.
1.turn the revolving turret so that low power lens come into position
2 place the microscope slide on the stage
3 look at the objective lens and the stage from the side as you turn adjust knob so that stage can move upward
4 look through the eyepiece and move the focus knob until image come into focus
5.adjust the condenser to regulate thee amount of light
6 move the microscope slide around until the sample is in the center of field of view
Scientists use carbon-14 to date ancient fossils.
Plants and animals absorb carbon-14 produced by cosmic rays. The ratio of C-14 to C-12 is constant when they are alive.
When they die, the C-14 decays to C-12, and the ratio changes.
Carbon-14 has a half-life of 5730 years. Thus, the object loses half its C-14 every 5730 years.
Scientists can use the C-14 to C-12 ratio to date fossils up to 70 000 years old.
