The energy change if 84.0 g of CaO react with excess water is 98KJ of heat is released.
calculation
heat = number of moles x delta H
delta H = - 65.2 Kj/mol
first find the number of moles of CaO reacted
moles = mass/molar mass
the molar mass of CaO = 40 + 16= 56 g/mol
mass = 84 g
moles therefore = 84 g/56 g/mol =1.5 moles
Heat is therefore = 1.5 moles x -65.2 = - 97.8 Kj = -98 Kj
since sign is negative the energy is released
Answer: A. an electron
<u>Beta particles are electrons or positrons (electrons with positive electric charge or antielectrons).</u> Beta decay is a type of radioactive decay in which a beta ray is emitted from an atomic nucleus.
<u>Beta decay occurs when, in an unstable nucleus with too many protons or too many neutrons, one of the protons or neutrons transforms into the other.</u> In beta minus decay, a neutron is broken down into a proton, an electron, and an antineutrino (the neutrino antiparticle, meaning it has an opposite charge to the neutrino). In beta decay plus, a prototype breaks down into a neutron, a positron and a neutrino.
Hi I need Help with this :
A swimming pool has an inlet pipe that can fill the empty pool in 12 hours with the drain is closed and the inlet pipe is closed the drain can empty the full pool in 20 hours. When the pool is empty how long will it take the inlet pipe to fill the pool drain if it is left open ?
Answer:
0.0187 M
Explanation:
Step 1: Write the balanced neutralization reaction
NaOH + HCl ⇒ NaCl + H₂O
Step 2: Calculate the reacting moles of HCl
18.7 mL of 0.01500 M HCl react.
0.0187 L × 0.01500 mol/L = 2.81 × 10⁻⁴ mol
Step 3: Calculate the reacting moles of NaOH
The molar ratio of HCl to NaOH is 1:1. The reacting moles of NaOH are 1/1 × 2.81 × 10⁻⁴ mol = 2.81 × 10⁻⁴ mol.
Step 4: Calculate the molarity of NaOH
2.81 × 10⁻⁴ moles are in 15.00 mL of NaOH.
[NaOH] = 2.81 × 10⁻⁴ mol/0.01500 L = 0.0187 M
Answer 2325 milligrams.
Explanation:The unit is abbreviated as tsp. Convert Milligrams (mg) to Teaspoons (tsp): 1 mg is approximately equal to 0.0002 tsps. One milligram is a relatively small quantity of table sugar A mere one-teaspoon of granulated sugar contains some 2325 milligrams.
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