Answer:
The elements in the alkaline earth metals group; beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra), have two electrons in their outer electronic shell.
Explanation:
Answer:
1.20atm
Explanation:
Given parameters:
Partial pressure of gas 1 = 0.35atm
Partial pressure of gas 2 = 0.20atm
Partial pressure of gas 3 = 0.65atm
Unknown:
Total pressure of the gas mixture = ?
Solution:
To solve this problem, we need to recall and understand the Dalton's law of partial pressure.
Dalton's law of partial pressure states that "the total pressure of a mixture of gases is equal to the sum of the partial pressure of the constituent gases".
Total pressure =Pressure of gas(1 + 2 + 3)
The partial pressure is the pressure a gas would exert if it alone occupied the volume of the gas mixture.
Now we substitute;
Total pressure = (0.35 + 0.20 + 0.65)atm = 1.20atm
43.8 has 3 significant figures and 1 decimal.
<h3 /><h3>What are significant figures?</h3>
The term significant figures refer to the number of important single digits (0 through 9 inclusive) in the coefficient of an expression in scientific notation.
All zeros that occur between any two non-zero digits are significant. For example, 108.0097 contains seven significant digits. All zeros that are on the right of a decimal point and also to the left of a non-zero digit are never significant. For example, 0.00798 contained three significant digits.
Hence, 43.8 has 3 significant figures and 1 decimal.
Learn more about significant figures here:
brainly.com/question/14359464
#SPJ1
Answer:
Because it can cause health problems or injuries to our sense organs.
Explanation:
Chemicals in the laboratory are made up of different constituents, which may be dangerous or injurious to health. This is the reason why safety measures or precautions have to be taken when working in the laboratory. One of those safety measures is that "one should never use taste, touch, or smell to identify an unknown chemical".
This is so because a chemical that is unknown amounts to the fact that what such chemical contains is unknown, hence, the chemical might have the ability to cause harm or injuries to the sense organ. For example, a conc. acid that is tasted will burn the tongue etc.
<span>Which part of the electromagnetic spectrum has a higher frequency than ultraviolet light? </span>B. Gamma Rays.
