Answer:
The answer to your question is 0.005
Explanation:
Data
Volume of NaOH = 25 ml
[NaOH] = 0.2 M
moles of NaOH = ?
To solve this problem is not necessary to have the chemical reaction. Just use the formula of Molarity and solve it for moles.
Formula
Molarity = moles / volume
-Solve for moles
moles = Molarity x volume
-Convert volume to liters
1000 ml ---------------- 1 l
25 ml ---------------- x
x = (25 x 1) / 1000
x = 0.025 l
-Substitution
moles = 0.2 x 0.025
-Result
moles = 0.005
Answer:
True
Explanation:
It is true that every element in the periodic table follows the Aufbau's principle.
The principle states that "the sublevels with lower energies are filled up before those with higher energies".
- Sublevels do not fill up in numerical order.
- This is true when writing the electronic configuration of all atoms on the periodic table.
Hi, here is a basic summary of what we did in a lab; there were 3 reactions: The procedure: Reaction 1: Solid sodium hydroxide dissolves in water to form an aqueous solution of ions. NaOH(s)-> Na+(aq) + OH-(aq) ΔH1=-34.121kJ Reaction 2: Solid sodium hydroxide reacts with an aqueous solution of HCl to form water and an aqueous solution of sodium chloride. NaOH(s) + H+(aq) + Cl-(aq) -> H2O + Na+(aq) + Cl-(aq) ΔH2=-83.602kJ Reaction 3: An aqueous solution of sodium hydroxide reacts with an aqueous solution of HCl to form water an an aqueous solution of sodium chloride. H+(aq) + OH-(aq) + Na+(aq) + Cl-(aq) -> H2O + Na+(aq) + Cl-(aq) ΔH3= -50.2kJ The ΔH values were calculated by dividing the heat gained by the number of moles (each reaction had 0.05moles of NaOH) The problem: Net ionic equations for reaction 2 & 3: 2: NaOH(s) + H+(aq) -> H2O + Na+(aq) 3: H+(aq) + OH-(aq) -> H2O i) In reaction 1, ΔH1 represents the heat evolved as solid NaOH dissolves. Look at the net ionic equations for reactions 2 and 3 and make similar statements as to what ΔH2 and ΔH3 represent. ii) Compare ΔH2 with (ΔH1 + ΔH3). Explain in sentences the similarity between these two values by using your answer to #5 above. Attempt at answering: i) Firstly, ΔH2 represents the heat evolved as the hydrogen ion displaces the sodium ion, creating a single displacement reaction. ΔH3 represents the heat evolved as the hydrogen and hydroxide ion form water via a neutralization reaction. ii) ΔH2 is equal to (or supposed to be, this is a source of error while calculating) (ΔH1 + ΔH3). The similarity between these two values is that .. (this is where I get confused!)
Source https://www.physicsforums.com/threads/calorimetry-help-chemistry.399653/
Answer: 5
Explanation: add up all the electrons and it will amount to 23. Arranging by the old model for electronic configuration, we have : 2, 8, 8, 5
The last number being 5 represent its valence electron
Answer: The actions that must have affected the igneous rock in order to form the sedimentary rock is that (It must have been broken down into sediments).
Explanation:
Rocks are solid structures that occurs naturally which is made up of different minerals. There are three main types of rocks, these includes:
--> METAMORPHIC ROCKS: These are the type of rocks which are formed by temperature and pressure changes inside the Earth.
--> SEDIMENTARY ROCKS: these rocks are usually formed from pre-existing rocks through the process of weathering (breaking down) of rocks.
--> IGNEOUS ROCKS: these rocks are formed when molten magma cools beneath or above the earth surface.
The actions that must have affected the igneous rock in order to form the sedimentary rock is that the igneous rocks are broken down into smaller pieces by erosion and weathering processes. Sediments which are formed accumulates at the earth surface. Over a long period of time, these sediments builds successive layers on top of one another. The sediments near the base hardens to form sedimentary rocks. This justifies the statement as a correct option (It must have been broken down into sediments).
