A unit of ppm has an acronym of parts per million. The
equivalent units of ppm is therefore mg/L and mg/kg. So the ppm is:
mass Ca+ = 1.3 g = 1300 mg
ppm = 1300 mg / 3100 kg
<span>ppm = 0.42 ppm</span>
The pressure of the CO₂ = 0.995 atm
<h3>Further explanation</h3>
The complete question
<em>A student is doing experiments with CO2(g). Originally, a sample of gas is in a rigid container at 299K and 0.70 atm. The student increases the temperature of the CO2(g) in the container to 425K.</em>
<em>Calculate the pressure of the CO₂ (g) in the container at 425 K.</em>
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Gay Lussac's Law
When the volume is not changed, the gas pressure is proportional to its absolute temperature

P₁=0.7 atm
T₁=299 K
T₂=425 K

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Answer:
Protons and neutrons which packed tightly into central core of the atom.
Explanation:
Atoms are composed of three subatomic particle; electron, proton and neutron. Electrons are negatively charged, protons are positively charged whereas neutrons are neutral, hence does not have any charge.
Out of three, protons and neutrons are present in the nucleus of the atom.
Nucleus is the central part of the atom possessing most of the mass of the atom. In the nucleus, protons and neutrons are tightly packed with the help of nuclear force.
Electrons are present around the nucleus also called electron cloud.
Therefore, nucleus are composed of protons and neutrons which packed tightly into central core of the atom
Answer:
b. independent/manipulated variable
Explanation:
Independent/manipulated variable - refers to the variable that is changed by the scientist or an experimenter. Only one variable that is independent is required to ensure a fair test in an excellent experiment. As the independent variable is being changed by an experimenter or scientist, data is being recorded simultaneously as they are collected.
A hypothesis is a prediction of what you believe to be true.