answer: -230kJ
When in doubt, use the google conversations! :)
Answer:
put a test tube over the opening, remove it and quickly put a lit splint near the mout or in the tube. if you hear a squeaky pop it is hydrogen.
Explanation:
hydrogen ignites in air.
The reaction will shift toward the reactants if the volume is cut in half.
<h3 /><h3>Reactants </h3>
The initial components of a chemical reaction are called reactants. Chemical bonds between reactants are broken and new ones are created in order to create products. Reactants and products are listed on the left and right sides, respectively, of the arrow in a chemical equation.
Substances on both sides of an arrow that points left and right are both reactants and products in a chemical process (the reaction proceeds in both directions simultaneously). A chemical equation that is balanced has the same amount of atoms of each element in the reactants and products. Around 1900–1920 is when the word "reactant" was first used. There are instances when the word "reagent" is interchangeable.
Learn more about reactants here:
brainly.com/question/17096236
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Answer:
Explanation:
Lewis dot structures represent the symbol of an atom we're looking at and the number of valence electrons it has. This number is represented by the sum of dots around the symbol.
- Potassium is in group 1A, this means it only has one valence electron, so we draw K with one dot in its Lewis diagram;
- Argon is in group 8A, this means it has eight valence electrons, so we draw Ar with 8 dots around it in its Lewis diagram;
- Silicon is in group 4A, this means it has four valence electrons, so we draw Si with 4 dots around it in its Lewis diagram;
- Arsenic is in group 5A, this means it has five valence electrons, so we draw As with 5 dots around it in its Lewis diagram.
Those are represented in the image attached below:
Answer:
D =Average atomic mass = 10.801 amu.
5) True
Explanation:
Abundance of B¹⁰= 19.9%
Abundance of B¹¹ = 80.1%
Atomic mass of B¹⁰ = 10 amu
Atomic mass of B¹¹ = 11 amu
Average atomic mass = ?
Solution:
Average atomic mass = (abundance of 1st isotope × its atomic mass) +(abundance of 2nd isotope × its atomic mass) / 100
Average atomic mass = (10×19.9)+(11×80.1) /100
Average atomic mass = 199 + 881.1 / 100
Average atomic mass = 1080.1 / 100
Average atomic mass = 10.801 amu.
2)A chemical reaction is one in which a new elements is created
True
False
Answer:
In chemical reaction new substances are created.
For example:
Photosynthesis:
It is the process in which in the presence of sun light and chlorophyll by using carbon dioxide and water plants produce the oxygen and glucose.
Carbon dioxide + water + energy → glucose + oxygen
water is supplied through the roots, carbon dioxide collected through stomata and sun light is capture by chloroplast.
Chemical equation:
6H₂O + 6CO₂ + energy → C₆H₁₂O₆ + 6O₂
it is known from balanced chemical equation that 6 moles of carbon dioxide react with the six moles of water and created one mole of glucose and six mole of oxygen.
