Making repeated separations of the various substances in the pitchblende, Marie and Pierre used the Curie electrometer to identify the most radioactive fractions. They thus discovered that two fractions, one containing mostly bismuth and the other containing mostly barium, were strongly radioactive.
<h3>What was surprising about pitchblende?</h3>
Since it was no longer appropriate to call them “uranic rays,” Marie proposed a new name: “radioactivity.”
Even more surprising, Marie next found that a uranium ore called pitchblende contained two powerfully radioactive new elements: polonium, which she named for her native Poland, and radium.
<h3>Why is radium more radioactive than uranium?</h3>
It is 2.7 million times more radioactive than the same molar amount of natural uranium (mostly uranium-238), due to its proportionally shorter half-life.
Learn more about highly radioactive elements here:
<h3>
brainly.com/question/10257016</h3><h3 /><h3>#SPJ4</h3>
Answer:
The law of definite proportions. I had the same question for chemistry and this is what they said was right so I got 100%.
Explanation:
Answer: Water is a permanent electric dipole, having permanent charge separation.
Explanation:
Hydrogen bonding is an intermolecular force having partial ionic-covalent character.
In , O is a highly electronegative atom attached to a H atom through a covalent bond. The oxygen atoms being more electronegative gets partial negative charge and H atom gets partial positive charge. Thus water is permanent electric dipole.
Hydrogen bonding takes place between a hydrogen atom (attached with an electronegative atom O) and an electronegative atom (O).
Answer:
Increasing the concentration of the reagents makes the collision between two molecules of the reagents more likely, thereby increasing the probability that the reaction will occur between these reagents.
As for the relationship between concentration and volume, density also comes into play, a higher volume, lower molarity and also lower concentration.
The pressure when increasing could generate a closer approach between the particles, therefore generating an increase in the reaction speed.
Pressure and volume are related but inversely proportional, therefore if the volume increases the pressure decreases and so on.
the reaction rate increases as the contact surface area increases. This is due to the fact that more solid particles are exposed and can be reached by reactant molecules.
A perfect reaction where the collision is promoted and the reaction speed advances is with the presence of a solvent, with an increase in pressure and a decrease in volume, with an increase in the exposure of the surface, with the presence of a catalyst, with increasing temperature and with increasing entrance
Explanation:
The reaction rate is defined as the amount of substance that is transformed into a certain reaction per unit of volume and time. For example, the oxidation of iron under atmospheric conditions is a slow reaction that can take many years but over time it is oxidized sooner or later by the oxygenation of its surface layer, but the combustion of butane in a fire is a reaction that happens in fractions of seconds, giving rise to an exothermic reaction with products such as CO2 and H2O