Answer is: <span>a hill over which a wagon is pushed.
</span>For all chemical
reaction some energy is required and that energy is called activation
energy (<span>energy
that needs to be absorbed for a chemical reaction to start)<span>.
There are two types of reaction: endothermic
reaction (chemical reaction that absorbs more energy than it releases)
and exothermic reaction (chemical reaction that releases more energy than
it absorbs).
</span></span>R<span>eactions
occur faster with a catalyst because they require less activation energy.</span>
Answer:
a.option is the correct answer
Answer:
moles H₂O = 10
Explanation:
The mass of Na₂CO₃⋅xH₂O is 3.837 g and the mass of Na₂CO₃ is 1.42g
Therefore the mass of xH₂O is 3.837 - 1.42 = 2.417 g
The molar mass of Na₂CO₃ is 106 g/mol and for H₂O is 18 g/mol
The moles of Na₂CO₃ and H₂O in the sample are:
Na₂CO₃ = 1.42 / 106 = 0.01340 moles
H₂O = 2.417 / 18 = 0.1343
Now using rule of three :
1 mole of Na₂CO₃ has x moles of H₂O
0.01340 moles of Na₂CO₃ has 0.1343 moles of H₂O
x = 1 * 0.1343 / 0.01340 = 10
Answer:
Star's
Explanation:
Stars have their own brightness
Covalent bonds formed when two atoms share an electron, as opposed to an Ionic bond where one atom takes an electron(or two) from another atom.