Step 1: Change density from g/mL to g/L;
0.807 g/mL = 807 g/L
Step 2: Find Moles of N₂;
As,
Density = Mass / Volume
Or,
Mass = Density × Volume
Putting Values,
Mass = 807 g/L × 1 L
Mass = 807 g
Also,
Moles = Mass / M.mass
Putting values,
Moles = 807 g / 28 g.mol⁻¹
Moles = 28.82 moles
Step 3: Apply Ideal Gas Equation to Find Volume of gas occupied,
As,
P V = n R T
V = n R T / P
Putting Values, remember! don't forget to change temperatue into Kelvin (25 °C + 273 = 298 K)
V = (28.82 mol × 0.08206 atm.L.mol⁻¹.K⁻¹ × 298 K) ÷ 1 atm
V = 704.76 L
<h2>Answer:</h2>
C) The scientist made an identification
<h2>Explanation:</h2>
The fingerprint is a very certain method for identifying a person, because all human beings have got unique fingerprints. Forensic laboratories have database of all citizens in the area. Hence an identification is done by the results matched with the database information. The two main categories of fingerprint matching techniques are minutiae-based matching and pattern matching and both are them are present in the given database.
Explanation:
The chemical formula of an ionic compound can be written by using the symbols of the respective cations and anions.
The overall charge on the molecule should be zero.
Hence, the total charge of cations=total charge of anions.
The symbols of the given molecules are shown below:
sodium chloride ---- NaCl
magnesium chloride ---
calcium oxide ---- CaO
lithium phosphide----
aluminum sulfide ----- 
calcium nitride---- 
Answer:
In aqueous solution the pH scale varies from 0 to 14, which indicates this concentration of hydrogen. Solutions with pH less than 7 are acidic (the value of the exponent of the concentration is higher, because there are more ions in the solution) and alkaline (basic) those with a pH higher than 7. If the solvent is pure water, the pH = 7 indicates neutrality of the solution
Explanation:
PH is a measure of how acidic or basic a liquid is. Specifically, from a dissolution. The acidity of a solution is essentially due to the concentration of hydrogen ions dissolved in it. In reality, the ions are not found alone, but are in the form of hydronium ions consisting of one oxygen molecule and three positively charged hydrogen. PH precisely measures this concentration. And to do it, we can use simple and very visual methods.
Technically, the answer is iron. Oxygen has a melting point way below zero (-219 degrees celsius), ice becomes water AT room temperature and bromine is already a liquid at room temperature. So, iron has a melting point greater than room temperature due to the fact that metals are made up of giant structures of atoms in a regular arrangement, and there are strong forces of electrostatic attraction between positive metal ions and negative electrons, meaning that a lot of heat energy is required to break the bonds, i.e. a very high melting point, approx. 1500 degrees celsius. Hope this helps.
