Answer: assume pathogens are present and treat the samples accordingly
Explanation:
When investigators are unable to conclusively ascertain the source of a biological sample found at a crime scene, the correct thing to do is to treat it as if pathogens are present in it and handle it according to set rules on how to handle pathogens.
This is done to ensure that if a pathogen is indeed present, it would not cause a health emergency by infecting those who come in contact with the samples at the scene.
17.93 grams of oxygen gas occupy 12.3L of space at 109.4 kPa and 15.4°C. Details about how to calculate mass can be found below.
<h3>How to calculate mass?</h3>
The mass of a given gas can be calculated by multiplying the number of moles of the substance by its molar mass.
However, the number of moles of the gas must be calculated first as follows:
PV = nRT
Where;
- P = pressure = 1.0796941atm
- V = volume = 12.3L
- n = number of moles
- T = temperature = 288.4K
- R = gas law constant = 0.0821 Latm/molK
1.079 × 12.3 = n × 0.0821 × 288.4
13.27 = 23.68n
n = 13.27/23.68
n = 0.56mol
Mass = 0.56 × 32
mass of oxygen gas = 17.93g
Therefore, 17.93 grams of oxygen gas occupy 12.3L of space at 109.4 kPa and 15.4°C.
Learn more about mass at: brainly.com/question/19694949
Answer:
Gallium, Phosphorus, Chlorine, Fluorine
Explanation:
Arrange the elements in order of increasing ionization energy. Use the periodic table to identify their positions on the table.
Drag each tile to the correct box.
Tiles
chlorinefluorinegalliumphosphorus
Sequence
Answer:
Hot chocolate is as straightforward as drinks go: at its core, it's milk, cocoa powder, and sugar. Despite its simplicity, this cold-weather classic is swirling with science. The backbone of any decent hot chocolate is milk. Beyond water, milk is perhaps the most basic and familiar substance to humans.
Answer:
B) 7.7
Explanation:
For the reaction Ag2CO3(s) + CrO42‒(aq) → Ag2CrO4(s) + CO32‒(aq)
Kc = (CO₃²⁻) / (CrO₄²⁻)
and the Ksp given are
Ag₂CO₃ ⇒ 2 Ag⁺(aq) + CO₃²⁻(aq) Ksp₁ = (Ag⁺)²(CO₃²⁻)
Ag₂CrO₄ ⇒ 2 Ag⁺(aq)+ CrO₄²⁻(aq) Ksp₂ = (Ag⁺)²(CrO₄²⁻)
Where (...) indicate concentrations M
Notice if we divide the expressions for Ksp we get:
Ksp₁/Ksp₂ = (CO₃²⁻) / (CrO₄²⁻) = 8.5 x 10⁻¹² / 1.1 x 10⁻¹² = 7.7
which is the desired answer.
