Chemistry Answers

How many moles are present in 24ml of 0.500m solution of sodium chloride

Write the thermochemical equation for the following reactions that occur at constant pressure.

1. Combustion of hexane, C5H12 to carbon dioxide gas and water, releases 3923.9kJ of heat.

2. Reaction between solid phosphorus, P4 and oxygen gas, produces P3O6 and 1640.1kJ of heat.

3. One mole ammonium nitrate (NH4NO3) dissolves in water to produce aqueous ammonium ions and nitrate ions accompanied by the absorption of 28.1kJ of heat.

4. Formation of carbon dioxide gas from carbon (graphite) and oxygen yields 393.5kJ of heat.

What are alkenes

How much MgCI2 will be produced in the reaction? Mg OH2 = 58.32g/mol , HCI = 36.46/mol , MgCI2 = 95.32/mol

element 35.3g of M reacts with nitrogen to form 43.5g of M3N2. whats the molar mass and name of the element M?

What is the % C by mass in aspirin?

A cache of Hebrew manuscripts known as the Dead Sea Scroll was found in 1947. The specific activity of Carbon-14 in the linen wrappings of the book of Isaiah was about 0.200 disintegration per second per gram (dps g-1.). Carbon-14 in living materials has

a specific activity of 0.255 dps g-1. The half-life of Carbon-14 is

5.73 x103 years. Carbon-14 decay by First order rate law. Calculate the approximate age of the linen.

How many grams of BaCl₂ should be added to 300 g H₂O so that the freezing point of the solution is lowered – 8.3 ⁰C ? Assume that the BaCl₂  completely dissociates in the solution.

1.      What will be the freezing point of an aqueous solution containing 80 g of NaCl? 

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A system has constant volume (∆V=0) and the heat around the system increases by 50 J

A. What is the sign for heat (q) for the system?

B. What is ∆V equal to?

C. What is the value of internal energy of the system in Joules?