They weigh less than the water they displace.
Whether things float or sink this depend only on the density , the density of the salt water is aprox. 1030 kilogram per meter cube so if you but things have density less than that they will float , things with higher density sink.
Things sink if they are heavy and push the water down, and float if they are light and let the water hold them up like a balloon.
It is quite common for various things to float in water. But any liquid can cause things to float.
You can't make things float, things float by it's self's it's density is lower than 1 it can float, if it's density is greater than 1 it can't float.
Helium is light and it will float / rise.
If it has enough surface area such as a leaf or bigger yes so long as it lands on the water in such a way it traps a little air under it, note..even concrete can float, many septic tanks are made of concrete and will float in only about a foot of water if you dont remember to fill them with water before it rains
Yes any salt can make things float
The term for the scientific explanation of how things float is "buoyancy."
it will float bc the penny is so light that it should float.
No. To get them to float they must be placed on something light.
What Makes Things Float - 1951 was released on: USA: 1951
Helium is a very light unreactive gas so it can be used in balloons etc.